State
of
California
AIR
RESOURCES
BOARD
STAFF
REPORT:
INITIAL
STATEMENT
OF
REASONS
FOR
PROPOSED
RULEMAKING
Engine
Manufacturer
Diagnostic
System
Requirements
for
2007
and
Subsequent
Model
Year
Heavy­
Duty
Engines
(
EMD)

Date
of
Release:
April
2,
2004
Scheduled
for
Consideration:
May
20,
2004
Mobile
Source
Control
Division
9528
Telstar
Avenue
El
Monte,
California
91731
www.
arb.
ca.
gov
This
document
has
been
reviewed
by
the
staff
of
the
California
Air
Resources
Board.
Publication
does
not
signify
that
the
contents
necessarily
reflect
the
views
and
policies
for
the
Air
Resources
Board.
Table
of
Contents
I.
EXECUTIVE
SUMMARY................................................................................................
1
II.
INTRODUCTION
AND
BACKGROUND
INFORMATION
...............................................
2
Introduction........................................................................................................................
2
Why
Require
OBD
Systems
on
Heavy­
Duty
Vehicles
and
Engines?.................................
3
What
Would
the
Heavy­
Duty
EMD
Regulation
Require?...................................................
4
What
Do
the
Federal
Regulations
Require?
......................................................................
5
III.
GENERAL
MONITORING
REQUIREMENTS................................................................
6
A.
Monitoring
Conditions...................................................................................................
6
B.
MIL
Requirements
........................................................................................................
6
IV.
PROPOSED
MONITORING
SYSTEM
REQUIREMENTS.............................................
6
A.
FUEL
SYSTEM
MONITORING
....................................................................................
6
B.
EGR
SYSTEM
MONITORING......................................................................................
7
C.
PM
TRAP
MONITORING
.............................................................................................
8
D.
EMISSION­
RELATED
ELECTRONIC
COMPONENT
MONITORING..........................
9
V.
CERTIFICATION
REQUIREMENTS
............................................................................
11
VI.
DEFICIENCIES............................................................................................................
11
VII.
ANALYSIS
OF
ENVIRONMENTAL
IMPACTS
AND
ENVIRONMENTAL
JUSTICE
ISSUES
.............................................................................................................................
11
VIII.
COST
IMPACT
OF
THE
PROPOSED
REQUIREMENTS
...........................................
12
A.
Cost
of
the
Proposed
Requirements...........................................................................
12
B.
Cost
Effectiveness
of
the
Proposed
Requirements
....................................................
12
IX.
ECONOMIC
IMPACT
ANALYSIS
................................................................................
13
A.
Legal
requirements.....................................................................................................
13
B.
Affected
businesses
and
potential
impacts.................................................................
13
C.
Potential
impacts
on
vehicle
operators
.......................................................................
13
D.
Potential
impacts
on
business
competitiveness..........................................................
14
E.
Potential
impact
on
employment.................................................................................
14
F.
Potential
impact
on
business
creation,
elimination,
or
expansion...............................
14
REFERENCES...................................................................................................................
15
1
I.
EXECUTIVE
SUMMARY
On­
board
diagnostics
(
OBD)
systems
are
comprised
mainly
of
software
designed
into
the
vehicle's
on­
board
computer
to
detect
emission
control
system
malfunctions
as
they
occur
by
monitoring
virtually
every
component
and
system
that
can
cause
increases
in
emissions.
When
an
emission­
related
malfunction
is
detected,
the
OBD
system
alerts
the
vehicle
owner
by
illuminating
the
malfunction
indicator
light
(
MIL)
on
the
instrument
panel.
By
alerting
the
owner
of
malfunctions
as
they
occur,
repairs
can
be
sought
promptly,
which
results
in
fewer
emissions
from
the
vehicle.
Additionally,
the
OBD
system
stores
important
information,
including
identifying
the
faulty
component
or
system
and
the
nature
of
the
fault,
which
would
allow
for
quick
diagnosis
and
proper
repair
of
the
problem
by
technicians.
This
helps
owners
achieve
less
expensive
repairs
and
promotes
repairs
done
correctly
the
first
time.

California
OBD
regulations
require
all
1996
and
newer
model
year
passenger
cars,
light­
duty
trucks,
and
medium­
duty
vehicles
and
engines
to
be
equipped
with
OBD
systems
(
referred
to
as
OBD
II).
However,
there
are
currently
no
equivalent
requirements
for
heavy­
duty
vehicles
(
i.
e.,
vehicles
with
a
gross
vehicle
weight
rating
greater
than
14,000
pounds).
Staff
has
begun
development
of
OBD
requirements
that
would
be
equally
effective
as
the
OBD
II
requirements,
and
plans
to
present
them
for
Board
consideration
in
2005.
In
the
meantime,
staff
has
worked
with
industry
to
come
up
with
an
interim
/
first
step.
These
proposed
requirements,
referred
to
as
the
engine
manufacturer
diagnostic
system
(
EMD)
regulation,
build
on
the
basic
engine
diagnostic
system
heavy­
duty
engine
manufacturers
are
currently
using
to
provide
diagnostic
capability
for
the
most
important
emission
control
systems.
Sufficient
lead
time
exists
to
implement
the
EMD
system
by
the
2007
model
year
when
emission
standards
become
more
stringent
and
universal
use
of
particulate
filters
is
expected.
Because
the
proposed
interim
diagnostics
does
not
approach
the
capabilities
and
sophistication
of
the
OBD
systems
used
on
current
light­
duty
vehicles,
it
is
referred
to
as
EMD
requirements,
and
the
term
OBD
will
be
reserved
for
use
in
the
comprehensive
OBD
proposal
next
year.

The
Air
Resources
Board
staff
is
proposing
the
adoption
of
section
1971,
title
13,
California
Code
of
Regulations
that
would
require
all
2007
and
subsequent
model
year
heavy­
duty
Otto­
cycle
(
gasoline)
and
diesel
engines
to
be
equipped
with
diagnostic
systems.
The
proposed
EMD
regulation,
which
is
included
herewith
as
Attachment
A,
would
require
manufacturers
to
monitor
the
fuel
system,
exhaust
gas
recirculation
system,
particulate
matter
trap,
and
emission­
related
electronic
components.
The
EMD
system
would
help
ensure
that
the
engines
are
able
to
meet
these
standards
and
maintain
low
emissions
for
the
life
of
the
engine.
It
would
accomplish
this
by
monitoring
the
durability
and
performance
of
the
emission
control
components
and
systems,
and
by
providing
technicians
with
information
that
would
help
in
diagnosing
and
fixing
malfunctions.
2
II.
INTRODUCTION
AND
BACKGROUND
INFORMATION
Introduction
On­
board
diagnostics
(
OBD)
systems
are
comprised
mainly
of
software
designed
into
the
vehicle's
on­
board
computer
to
detect
emission­
control
system
malfunctions
as
they
occur.
This
is
done
by
monitoring
virtually
every
component
and
system
that
can
cause
increases
in
emissions.
With
a
couple
of
exceptions,
no
additional
hardware
is
required
to
perform
the
monitoring;
rather,
the
powertrain
control
computer
is
designed
to
better
evaluate
the
electronic
component
signals
that
are
already
available,
thereby
minimizing
any
added
hardware
complexity.
When
an
emission­
related
malfunction
is
detected,
the
OBD
system
alerts
the
vehicle
operator
by
illuminating
the
malfunction
indicator
light
(
MIL)
on
the
instrument
panel.
By
alerting
the
operator
of
malfunctions
as
they
occur,
repairs
can
be
sought
promptly,
which
results
in
fewer
emissions
over
the
life
of
the
vehicle.
Additionally,
the
OBD
system
stores
important
information,
including
identifying
the
faulty
component
or
system
and
the
nature
of
the
fault,
which
would
allow
for
quick
diagnosis
and
proper
repair
of
the
problem
by
technicians.
This
helps
vehicle
owners
achieve
less
expensive
repairs
and
promotes
repairs
being
done
correctly
the
first
time.

Currently,
California
regulations
require
all
1996
and
newer
passenger
cars,
lightduty
trucks,
and
medium­
duty
vehicles
and
engines
to
be
equipped
with
OBD
systems
(
referred
to
as
OBD
II
systems).
The
Air
Resources
Board
(
ARB)
first
adopted
the
OBD
II
regulation
(
title
13,
California
Code
of
Regulations
(
CCR)
section
1968.1)
in
1989
and
subsequently
modified
the
regulation
in
regular
updates
in
later
years
to
address
manufacturers'
implementation
concerns
and
strengthen
specific
monitoring
requirements,
among
other
reasons.
In
2002,
ARB
amended
the
OBD
II
regulation
by
adopting
title
13,
CCR
sections
1968.2
and
1968.5,
which
established
OBD
II
requirements
and
an
OBD
II­
specific
in­
use
enforcement
protocol,
respectively,
for
2004
and
subsequent
model
year
passenger
cars,
light­
duty
trucks,
and
medium­
duty
vehicles
and
engines.

The
OBD
II
requirements
serve
an
important
role
in
achieving
and
maintaining
low
vehicle
emissions.
Manufacturers
are
required
to
improve
their
emission
control
system
performance
and
durability
in
order
to
meet
the
very
low
and
near­
zero
emission
standards
of
the
Low
Emission
Vehicle
II
program.
Since
the
OBD
II
program
is
designed
to
ensure
maximum
emission
control
system
performance
for
the
entire
life
of
the
vehicles
(
regardless
of
mileage),
it
is
able
to
monitor
the
low­
emission
performance
of
vehicles
and
ensure
that
they
are
performing
as
required
throughout
their
useful
lives
and
beyond.
This
is
important,
since
most
emission
problems
occur
as
vehicles
age
and
accumulate
high
mileage.
Input
from
manufacturers,
service
technicians,
Inspection
and
Maintenance
(
I/
M)
programs,
and
in­
use
evaluation
programs
indicate
that
the
OBD
II
program
is
very
effective
in
finding
emission
problems
and
facilitating
repairs.
The
United
States
Environmental
Protection
Agency
(
U.
S.
EPA),
in
fact,
issued
a
final
rule
that
indicates
its
confidence
in
the
performance
of
OBD
II
systems
by
requiring
states
to
perform
OBD
II
checks
for
these
newer
vehicles
and
allowing
them
to
3
be
used
in
lieu
of
current
tailpipe
tests
in
I/
M
programs.
Overall,
ARB
staff
is
pleased
with
the
significant
and
effective
efforts
of
the
automotive
industry
in
implementing
the
program
requirements.

Why
Require
OBD
Systems
on
Heavy­
Duty
Vehicles
and
Engines?

Heavy­
duty
vehicles
are
an
important
part
of
the
country's
transportation
network.
Due
to
their
fuel
efficiency,
maintenance
costs,
and
durability,
diesel
engines
are
employed
on
the
vast
majority
of
the
heavy­
duty
trucks
in
lieu
of
gasoline
engines.
Unfortunately,
the
emissions
emitted
from
these
heavy­
duty
trucks,
especially
diesel
trucks,
are
of
great
concern.
Currently,
diesel
truck
emissions
account
for
about
28
percent
and
16
percent
of
the
total
statewide
mobile
source
oxides
of
nitrogen
(
NOx)
and
particulate
matter
(
PM)
emissions,
respectively.
NOx
is
a
precursor
to
ozone
and
atmospheric
PM
as
well
as
a
lung
irritant,
while
diesel
PM
is
carcinogenic
and
has
been
identified
as
a
toxic
air
contaminant
by
ARB.
While
emissions
from
heavy­
duty
diesels
are
of
particular
concern,
emissions
from
heavy­
duty
gasoline
vehicles
are
also
of
concern,
given
the
state's
ongoing
challenge
in
meeting
state
and
federal
ambient
air
quality
standards.

As
stated
previously,
OBD
systems
are
required
on
all
1996
and
newer
passenger
cars,
light­
duty
trucks,
and
medium­
duty
vehicles
and
engines.
Presently,
however,
there
are
no
regulations
in
California
requiring
OBD
systems
on
heavy­
duty
vehicles
(
i.
e.,
vehicles
with
a
gross
vehicle
weight
rating
greater
than
14,000
pounds).
Staff
has
begun
development
of
OBD
requirements
that
would
be
equally
effective
as
the
OBD
II
requirements
and
plans
to
present
them
for
Board
consideration
in
2005.
In
the
meantime,
staff
has
worked
with
industry
to
come
up
with
an
interim
/
first
step.
ARB
staff
is
proposing
the
adoption
of
title
13,
CCR
section
1971
that
would
require
manufacturers
to
implement
diagnostic
systems
on
all
2007
and
subsequent
model
year
heavy­
duty
Otto­
cycle
(
gasoline)
and
diesel
engines.
These
proposed
requirements,
referred
to
as
the
engine
manufacturer
diagnostic
system
(
EMD)
regulation
(
proposed
title
13,
CCR
section
1971),
build
on
the
basic
diagnostic
system
heavy­
duty
engine
manufacturers
are
currently
using
to
provide
diagnostic
capability
for
the
most
important
emission
control
systems.
Sufficient
leadtime
exists
to
implement
the
EMD
program
by
the
2007
model
year
when
emission
standards
become
more
stringent
and
universal
use
of
particulate
filters
is
expected.
It
does
not,
however,
reflect
the
level
of
diagnostics
that
staff
will
be
pursuing
at
a
later
date
for
future
OBD
requirements
and,
as
such,
is
referred
to
as
EMD
while
the
term
OBD
will
be
reserved
for
use
in
the
comprehensive
OBD
proposal
next
year.

The
reasons
for
requiring
OBD
systems
on
heavy­
duty
vehicles
and
engines
are
analogous
to
those
for
requiring
OBD
II
systems
on
light­
and
medium­
duty
vehicles.
Like
the
light­
and
medium­
duty
vehicles,
the
emission
standards
for
heavy­
duty
vehicles
have
become
increasingly
stringent
over
the
years.
By
2004,
the
heavy­
duty
diesel
emission
standards
for
NOx
and
PM
have
been
reduced
by
60
to
80
percent
compared
to
the
standards
in
1990.
In
2007,
both
emission
standards
would
be
reduced
further
by
90
percent
compared
to
the
2004
standards.
Emission
standards
for
4
heavy­
duty
gasoline
vehicles
and
engines
are
also
similarly
reduced
beginning
in
2008.
While
the
adoption
of
increasingly
stringent
standards
are
a
step
towards
meeting
California's
air
quality
goals,
there
must
be
some
assurance
that
these
standards
continue
to
be
met
in­
use,
since
emission­
related
malfunctions
can
cause
vehicle
emissions
to
increase
well
beyond
the
standards
that
they
are
intended
to
meet.
To
meet
these
stringent
standards,
manufacturers
must
improve
existing
emission
control
technologies
as
well
as
utilize
new
technologies.
The
technologies
include
combinations
of
electronic
powertrain
and
emission
controls
as
well
as
exhaust
aftertreatment
components.
Accordingly,
in
order
to
maintain
low
emissions
throughout
the
vehicle's
life,
the
durability
and
performance
of
these
components
and
systems
must
be
monitored.
Additionally,
with
these
changes
comes
the
development
of
more
complex
electronic
emission
control
systems,
which
increasingly
rely
on
computerbased
control.
Therefore,
the
diagnosing
of
malfunctions
related
to
emission­
related
components
and
systems
becomes
more
complicated
as
well.
OBD
systems
would
ensure
that
emission­
related
malfunctions
are
quickly
detected
as
well
as
properly
identified
and
repaired
by
providing
repair
technicians
with
information
concerning
the
malfunctioning
component
and
the
type
of
failure
present.

Recognizing
the
strict
compliance
schedule
facing
engine
manufacturers
to
meet
the
stringent
2007
model
year
emission
standards
and
the
continued
developments
in
new
and
emerging
emission
control
technologies,
the
ARB
staff
is
not
proposing
the
immediate
development
of
comprehensive
OBD
systems
that
require
the
monitoring
of
every
emission­
related
component
in
the
vehicle.
Thus,
the
proposed
EMD
regulation
for
the
2007
model
year
includes
requirements
that
are
less
comprehensive
than
an
OBD
regulation.
Specifically,
it
would
require
functional
monitoring
of
major
emission
control
components/
systems
but
would
not
set
standardization
requirements
for
the
emission­
related
information
that
is
to
be
provided
by
the
EMD
system,
nor
would
it
tie
OBD
warnings
to
specific
emission
levels.
The
proposed
EMD
regulation
is
intended
to
be
the
first
step
towards
adopting
comprehensive
heavy­
duty
OBD
requirements
analogous
to
the
OBD
II
regulation
adopted
for
light­
duty
and
medium­
duty
vehicles.
The
heavy­
duty
OBD
regulation,
scheduled
for
a
Board
hearing
next
year,
would
provide
for
comprehensive
monitoring
tied
to
emission
levels,
standardized
monitoring
requirements
to
assist
in
repairs,
and
a
mechanism
to
assure
the
OBD
system
functions
frequently
in
the
field.

What
Would
the
Heavy­
Duty
EMD
Regulation
Require?

As
stated
above,
the
proposed
heavy­
duty
EMD
regulation
would
require
all
2007
model
year
heavy­
duty
gasoline
and
diesel
engines
to
be
equipped
with
EMD
systems.
Manufacturers
would
be
required
to
perform
functional
monitoring
of
the
fuel
system,
exhaust
gas
recirculation
(
EGR)
system,
and
PM
trap.
Additionally,
manufacturers
would
also
be
required
to
monitor
any
emission­
related
electronic
component
for
proper
function.
For
example,
for
components
that
provide
input
to
the
on­
board
computer,
the
EMD
system
would
generally
be
required
to
monitor
for
out­
of­
range
values
(
generally
open
or
short
circuit
malfunctions)
and
input
values
that
are
not
reasonable
based
on
other
information
available
to
the
computer
(
e.
g.,
sensor
readings
that
are
stuck
at
a
5
particular
value
or
biased
significantly
from
the
correct
value).
For
output
components
that
receive
commands
from
the
on­
board
computer,
the
EMD
system
would
generally
be
required
to
monitor
for
proper
function
in
response
to
these
commands
(
e.
g.,
the
system
verifies
that
a
valve
actually
opens
and
closes
when
commanded
to
do
so).
Monitoring
of
these
components
is
important,
since
the
EMD
system
relies
on
many
of
these
components
to
perform
monitoring
of
the
more
critical
emission
control
devices.
When
a
malfunction
of
any
of
the
systems/
components
mentioned
above
is
detected,
the
proposed
regulation
would
require
the
diagnostic
system
to
alert
the
operator
to
the
problem
by
illuminating
a
warning
light.

The
proposed
regulation
would
not
require
the
monitoring
of
aftertreatment
technologies
(
e.
g.,
catalysts,
NOx
adsorbers/
traps)
other
than
PM
traps.
At
this
time,
however,
the
absence
of
monitoring
is
not
a
great
concern.
Based
on
discussions
with
industry,
engine
manufacturers
are
not
expected
to
utilize
NOx
aftertreatment
in
order
to
meet
the
2007
standards.
Thus,
widespread
usage
of
NOx
aftertreatment
on
heavyduty
engines
is
not
anticipated
until
later
than
the
2007
model
year
(
possibly
to
meet
the
2010
standards).
Additionally,
manufacturers
planning
to
implement
selective
catalytic
reduction
systems
in
the
2007
timeframe
are
required
under
federal
regulations
to
establish
safeguards
(
under
40
Code
of
Federal
Regulations
Part
86)
to
help
ensure
proper
operation
of
the
systems.
Under
these
requirements,
manufacturers
would
need
to
demonstrate
that,
among
other
things,
an
adequate
urea
infrastructure
is
in
place
(
e.
g.,
ensuring
the
availability
of
urea)
and
measures
against
tampering
are
in
place.
While
these
safeguards
help
mitigate
the
absence
of
specific
monitoring
requirements
currently,
they
do
not
offer
"
complete"
protection
from
malfunctions
of
the
systems,
which
ARB
intends
to
address
with
its
future
comprehensive
OBD
requirements.
For
noncompliances,
manufacturers
will
be
subject
to
enforcement
under
the
applicable
provisions
of
the
Health
and
Safety
Code.

What
Do
the
Federal
Regulations
Require?

Currently,
the
U.
S.
EPA
only
has
OBD
requirements
for
light­
duty
vehicles
and
trucks
and
for
federally
defined
"
heavy­
duty"
vehicles
and
engines
with
a
gross
vehicle
weight
rating
(
GVWR)
between
8,500
to
14,000
pounds.
These
are
the
same
categories
of
vehicles
covered
by
ARB's
OBD
II
regulations
which
apply
to
light­
and
medium­
duty
vehicles
(
where
medium­
duty
is
defined
in
California
as
the
8,500
to
14,000
pound
GVWR
range).
Presently,
like
ARB,
the
U.
S.
EPA
does
not
have
OBD
requirements
for
vehicles
and
engines
above
14,000
pounds,
which
is
the
weight
range
for
California's
"
heavy­
duty"
class.
ARB
staff
and
the
U.
S.
EPA
staff
have
been
discussing
the
heavy­
duty
requirements
and
the
U.
S.
EPA
staff
has
indicated
its
intent
to
propose
and
adopt
a
regulation
for
heavy­
duty
vehicles
and
engines
over
14,000
pounds.
U.
S.
EPA
staff
have
indicated
a
strong
interest
in
working
with
ARB,
the
heavy­
duty
industry,
and
other
stakeholders
to
develop
harmonized
ARB
and
federal
programs.
6
III.
GENERAL
MONITORING
REQUIREMENTS
A.
Monitoring
Conditions
As
stated
previously,
the
intent
of
the
EMD
system
is
to
detect
malfunctions
of
the
emission
control
system.
Accordingly,
manufacturers
are
required
to
define
all
monitoring
conditions
necessary
to
allow
for
proper
detection
of
malfunctioning
components.

B.
MIL
Requirements
The
EMD
system
would
also
be
required
to
illuminate
a
warning
light(
s)
upon
detection
of
an
emission­
related
malfunction.
Manufacturers
would
have
the
flexibility
to
utilize
a
dedicated
light
or
an
existing
warning
light(
s)
as
long
as
it
would
be
likely
to
cause
the
vehicle
operator
to
seek
corrective
action
(
e.
g.,
repair).
Lastly,
to
verify
the
integrity
of
the
warning
light
itself,
the
EMD
system
would
be
required
to
perform
a
bulb
check
by
illuminating
the
warning
light
in
the
key
on,
engine
off
position
prior
to
engine
cranking.
This
would
allow
a
technician
or
vehicle
operator
to
ensure
the
MIL
is
capable
of
illuminating
by
simply
cycling
the
key
on.

IV.
PROPOSED
MONITORING
SYSTEM
REQUIREMENTS
A.
FUEL
SYSTEM
MONITORING
Background
An
important
component
in
emission
control
is
the
fuel
system.
Proper
delivery
of
fuel
can
play
a
crucial
role
in
maintaining
low
engine­
out
emissions.
The
performance
of
the
fuel
system
is
also
critical
for
exacting
optimum
performance
from
other
emission
controls.
As
such,
monitoring
of
the
fuel
system
is
an
essential
element
of
the
EMD
system.

A
substantial
change
has
occurred
in
recent
years
as
most
manufacturers
have
transitioned
to
(
or
are
currently
working
on)
new
high­
pressure
fuel
systems.
One
of
the
most
widely
used
is
a
"
common­
rail"
fuel
injection
system,
which,
unlike
an
older
style
fuel
system,
is
capable
of
controlling
to
any
desired
fuel
pressure
independent
of
engine
speed.
Increased
fuel
pressure
control
allows
greater
precision
relative
to
fuel
quantity
and
fuel
injection
timing,
and
provides
engine
manufacturers
with
tremendous
flexibility
in
optimizing
the
performance
and
emission
characteristics
of
the
engine.
While
most
diesel
engine
manufacturers
use
common­
rail
systems,
some
use
improved
unit
injector
systems.
In
these
systems,
fuel
pressure
is
generated
within
the
injector
itself
rather
than
via
an
electric
fuel
pump
in
a
common­
rail
system.
Earlier
versions
of
unit
injector
systems
were
limited
in
the
pressure
that
could
be
achieved
(
since
the
fuel
pressure
was
a
function
of
engine
speed
and
could
not
be
modified
apart
from
a
change
in
engine
speed),
but
newer
design
iterations
have
created
an
injector
with
extra
valves
that
allow
the
system
to
deliver
higher
or
lower
pressures
at
a
given
engine
speed,
thus
7
enabling
the
fuel
system
to
achieve
much
of
the
same
fuel
pressure
range
a
commonrail
system
is
capable
of
achieving.

Proposed
Monitoring
Requirements
Given
the
complexity
and
importance
of
proper
fuel
pressure
control,
the
proposed
requirements
target
malfunctions
that
would
prevent
proper
control
of
the
fuel
system
pressure.
Accordingly,
if
the
engine
is
equipped
with
feedback
control
of
the
fuel
pressure,
the
proposed
regulation
would
require
the
EMD
system
to
indicate
a
malfunction
when
the
fuel
system
has
reached
its
control
limits
(
i.
e.,
has
used
up
all
the
adjustments
allowed)
such
that
it
cannot
achieve
the
target
fuel
pressure.

Technical
Feasibility
of
Proposed
Monitoring
Requirements
For
diesel
engines,
under
the
light­
and
medium­
duty
OBD
II
requirements,
a
few
passenger
cars
and
several
medium­
duty
applications
utilizing
diesel
engines
have
been
monitoring
the
fuel
system
components
since
the
1997
model
year.
Recently,
this
has
included
vehicles
using
common­
rail
fuel
injection
and
improved
unit
injector
systems,
the
same
new
technology
expected
to
be
used
throughout
the
heavy­
duty
industry.
Manufacturers
(
including
half
of
the
heavy­
duty
engine
manufacturers)
have
been
able
to
meet
the
more
stringent
OBD
II
monitoring
requirements
on
medium­
duty
applications.
Thus,
the
technical
feasibility
for
the
less
stringent
EMD
requirements
has
been
demonstrated.

B.
EGR
SYSTEM
MONITORING
Background
EGR
is
one
of
the
most
effective
emission
control
technologies
for
reducing
NOx
emissions
in
vehicles
today.
Generally,
NOx
emissions
are
formed
under
high
combustion
chamber
temperature
and
pressure
conditions.
EGR
systems
redirect
spent
combustion
gases
from
the
exhaust
stream
to
the
intake
system
to
dilute
the
oxygen
concentration
and
increase
the
heat
capacity
of
the
air/
fuel
charge.
This
effectively
reduces
the
combustion
temperature,
which
results
in
lower
levels
of
NOx
emissions.
For
diesel
engines
especially,
EGR
systems
have
become
more
commonplace
and
will
likely
be
a
key
emission
control
component
in
helping
heavy­
duty
diesel
engines
meet
the
future
stringent
emission
standards.

Proposed
Monitoring
Requirements
The
proposed
regulation
would
require
the
EMD
system
to
indicate
an
EGR
system
malfunction
when
the
system
has
reached
its
control
limits
(
i.
e.,
cannot
increase
or
decrease
EGR
flow)
such
that
it
cannot
achieve
the
commanded
EGR
flow
(
i.
e.,
the
flow
is
either
too
low
or
too
high).
8
Technical
Feasibility
of
Proposed
Monitoring
Requirements
The
light­
and
medium­
duty
OBD
II
regulations
have
required
EGR
system
monitoring
to
more
stringent
levels
since
the
1996
model
year.
The
technical
feasibility
of
EGR
monitoring
has
already
been
demonstrated
for
these
applications
which
include
diesel
engines
built
by
half
of
the
heavy­
duty
engine
manufacturers
for
use
in
mediumduty
applications.

C.
PM
TRAP
MONITORING
Background
As
indicated
earlier,
the
PM
emission
standards
for
the
2007
model
year
will
be
reduced
by
90
percent
from
the
2004
model
year
standards.
In
order
to
meet
the
increasingly
stringent
standards,
manufacturers
will
likely
use
aftertreatment
devices
such
as
PM
traps
to
achieve
the
necessary
emission
levels.
PM
traps
are
considered
the
most
effective
control
technology
for
the
reduction
of
particulate
emissions
and
can
typically
achieve
PM
reductions
in
excess
of
90
percent.
In
general,
a
PM
trap
consists
of
a
filter
material
that
permits
exhaust
gases
to
pass
through
but
traps
the
particulate
matter.
In
order
to
maintain
the
performance
of
the
PM
trap
and
the
vehicle,
the
trapped
PM
must
be
periodically
removed
before
too
much
particulate
is
accumulated
and
exhaust
backpressure
reaches
unacceptable
levels.
The
process
of
periodically
removing
accumulated
PM
from
the
trap
is
known
as
regeneration
and
is
very
important
for
maintaining
low
PM
emission
levels.
PM
trap
regeneration
can
be
passive
(
i.
e.,
occur
continuously
during
regular
operation
of
the
filter),
active
(
i.
e.,
occur
periodically
after
a
predetermined
quantity
of
particulates
have
been
accumulated),
or
a
combination
of
the
two.
With
passive
regeneration,
oxidation
catalyst
material
is
typically
placed
on
the
PM
trap
system
to
lower
the
temperature
for
oxidizing
PM.
This
allows
the
trap
to
continuously
oxidize
trapped
PM
material
during
normal
driving.
In
contrast,
active
systems
utilize
an
external
heat
source
such
as
an
electric
heater
or
fuel
burner
to
facilitate
PM
trap
regeneration.
It
is
projected
that
virtually
all
PM
trap
systems
will
have
some
sort
of
active
regeneration
mechanism.

One
of
the
key
factors
that
needs
to
be
taken
into
account
for
a
trap
regeneration
control
system
is
the
amount
of
soot
quantity
that
is
stored
in
the
PM
trap
(
often
called
soot
loading).
1
If
too
much
soot
is
stored
in
the
PM
trap
when
regeneration
is
activated,
the
soot
can
burn
uncontrollably
and
damage
the
filter.
However,
activating
regeneration
when
there
is
too
little
trapped
soot
is
also
undesirable
since
there
is
a
minimum
amount
of
soot
quantity
needed
to
ensure
good
combustion
propagation.
Another
important
factor
to
be
considered
in
the
control
system
design
is
the
fuel
economy
penalty
involved
with
trap
regeneration.
Prolonged
operation
with
high
backpressures
in
the
exhaust
and
too
frequent
regenerations
are
both
detrimental
to
fuel
economy
and
durability.
Therefore,
trap
designers
will
need
to
carefully
balance
the
regeneration
frequency
with
various
conflicting
factors.
In
order
to
optimize
the
trap
1
Salvat,
O.,
Marez,
P.,
and
Belot,
G.,
"
Passenger
Car
Serial
Application
of
a
Particulate
Filter
System
on
a
Common
Rail
Direct
Injection
Diesel
Engine,"
SAE
Paper
2000­
01­
0473.
9
regeneration
for
these
design
factors,
the
control
system
for
the
regeneration
system
is
projected
to
utilize
both
pressure
sensors
and
temperature
sensors
to
model
soot
loading
among
other
properties.
1
Through
the
information
provided
by
these
sensors,
designers
can
optimize
the
PM
trap
for
high
effectiveness
and
maximum
durability
while
minimizing
fuel
economy
and
performance
penalties.

Proposed
Monitoring
Requirements
The
proposed
regulation
would
require
the
EMD
system
to
indicate
a
PM
trap
malfunction
when
the
PM
trap
fails
such
that
it
causes
the
backpressure
in
the
exhaust
system
to
exceed
the
manufacturer's
specified
limits
for
normal
operation.
Additionally,
manufacturers
would
be
required
to
indicate
a
malfunction
when
the
PM
trap
substrate
is
completely
destroyed,
removed,
or
missing,
or
if
the
PM
trap
assembly
is
replaced
with
a
straight
pipe.

Technological
Feasibility
of
Proposed
Monitoring
Requirements
It
is
anticipated
that
manufacturers
will
not
need
additional
hardware
to
meet
the
PM
trap
monitoring
requirements.
The
same
pressure
and
temperature
sensors
that
are
used
to
control
trap
regeneration
can
be
used
for
monitoring.
In
general,
a
pressure
sensor
placed
upstream
of
the
trap
(
or
a
differential
pressure
sensor
across
the
trap)
and
at
least
one
temperature
sensor
located
near
the
PM
trap
are
used
for
the
control
system.
As
mentioned
earlier,
pressure
sensors
are
expected
to
be
used
on
PM
trap
systems
to
prevent
damage
due
to
delayed
or
incomplete
regeneration
that
could
lead
to
excess
temperatures.
When
a
pressure
sensor
placed
upstream
of
the
trap
senses
high
backpressures,
active
regeneration
can
be
activated.
The
same
pressure
sensor
could
also
be
used
to
identify
the
presence
of
excessive
backpressure
and
indicate
a
malfunction.
To
detect
a
missing
or
destroyed
PM
trap,
the
same
backpressure
sensor
could
be
used
to
detect
too
little
backpressure.
With
a
properly
functioning
PM
trap,
a
minimum
level
of
backpressure
will
always
be
present
but
if
the
trap
is
missing
or
destroyed,
the
backpressure
will
fall
below
the
minimum
level.
Also,
backpressure
on
a
normal
PM
trap
should
progressively
increase
as
the
mass
of
soot
and
trapped
particles
increase.
In
general,
the
mass
of
soot
and
trapped
particles
should
increase
as
the
mileage
traveled
or
time
of
operation
increase.
However,
a
destroyed
or
missing
filter
will
not
cause
an
increase
in
backpressure
as
expected.
Therefore,
a
destroyed
or
missing
filter
can
alternatively
be
detected
if
the
backpressure
fails
to
increase
at
the
rate
projected
by
the
soot­
loading
model.
One
European
vehicle
manufacturer
has
already
incorporated
PM
trap
monitoring
on
their
PM
trap­
equipped
vehicles
since
2000.

D.
EMISSION­
RELATED
ELECTRONIC
COMPONENT
MONITORING
Background
Similar
to
the
OBD
II
requirements
for
light­
and
medium­
duty
vehicles,
the
staff
is
proposing
that
manufacturers
monitor
for
malfunctions
of
emission­
related
electronic
components
on
heavy­
duty
vehicles,
which
covers
all
other
electronic
powertrain
10
components
or
systems
not
mentioned
above
that
either
are
determined
by
the
manufacturer
to
be
emission­
related
or
are
used
as
part
of
the
EMD
diagnostic
strategy
for
another
monitored
component
or
system.
These
components
are
generally
identified
as
input
components,
which
provide
input
directly
or
indirectly
to
the
on­
board
computer,
or
as
output
components/
systems,
which
receive
commands
from
the
onboard
computer.
Typical
examples
of
input
components
include
temperature
sensors
and
pressure
sensors,
while
examples
of
output
components/
systems
include
the
idle
speed
control
system,
glow
plugs,
wait­
to­
start
lamps,
and
automatic
transmission
solenoid
or
controls.

While
the
emission
impact
of
malfunctioning
emission­
related
electronic
components
may
not
be
as
high
as
the
fuel
system,
EGR
system,
or
PM
trap,
they
still
could
result
in
a
measurable
increase
in
emissions.
With
the
heavy­
duty
emission
standards
becoming
increasingly
stringent
in
the
near
future,
manufacturers
need
to
ensure
that
their
emission­
control
systems
are
working
properly
in
order
to
meet
these
standards.
Furthermore,
the
proper
performance
of
these
components
can
be
critical
to
the
monitoring
strategies
of
other
components
or
systems.
Malfunctions
of
emissionrelated
electronic
components
that
go
undetected
by
the
EMD
system
may
disable
or
adversely
affect
the
robustness
of
other
EMD
monitors
without
any
indication.
This
could
potentially
result
in
the
failure
to
detect
other
faulty
emission­
related
components
or
systems.
Due
to
the
vital
role
these
components
play,
it
is
important
that
these
components
are
properly
monitored.

Proposed
Monitoring
Requirements
The
EMD
system
would
be
required
to
detect
malfunctions
of
all
electronic
components
that
are
emission­
related
or
are
used
for
other
EMD
monitors.
Where
feasible,
input
components
would
be
required
to
be
monitored
for
out­
of­
range
and
circuit
continuity
faults
(
shorts,
opens,
etc.)
as
well
as
rationality
faults
(
e.
g.,
where
a
sensor
reads
inappropriately
high
or
low
but,
unlike
out­
of­
range
faults,
still
within
the
valid
operating
range
of
the
sensor).
Rationality
monitoring
would
be
required
to
use
all
available
information
and
would
generally
be
accomplished
by
comparing
the
output
characteristics
of
multiple
sensors
that
read
the
same
metric
during
certain
engine
operating
conditions.

The
staff
is
proposing
that,
where
feasible,
output
components
be
monitored
for
proper
functional
response
(
i.
e.,
that
the
component
has
properly
carried
out
a
command
from
the
on­
board
computer)
and
for
proper
circuit
operation
(
i.
e.,
circuit
continuity
and
shorts).

Technical
Feasibility
of
Proposed
Monitoring
Requirements
The
light­
and
medium­
duty
OBD
II
regulations
have
required
emission­
related
electronic
component
monitoring
since
the
1996
model
year.
The
technical
feasibility
has
clearly
been
demonstrated
for
these
packages.
11
V.
CERTIFICATION
REQUIREMENTS
The
certification
requirements
would
require
manufacturers
of
EMD
systems
to
submit
an
application
for
each
EMD
system.
The
documentation
would
consist
of:
(
1)
a
description
of
the
functional
operation
of
the
EMD
system,
and
(
2)
a
listing
of
all
electronic
powertrain
input
and
output
signals
(
including
those
not
monitored
by
the
EMD
system)
and
identification
of
those
signals
that
are
monitored
by
the
EMD
system.

VI.
DEFICIENCIES
During
the
early
stages
of
OBD
implementation
for
light­
and
medium­
duty
vehicles,
some
manufacturers
encountered
unforeseen
and
generally
last­
minute
problems
with
some
monitoring
strategies
despite
a
good
faith
effort
to
comply
with
the
requirements
in
full.
The
staff
anticipates
the
same
problems
may
occur
during
heavyduty
EMD
implementation.
Thus,
the
staff
is
proposing
a
provision
that
would
permit
certification
of
heavy­
duty
EMD
systems
with
"
deficiencies"
in
cases
where
a
good
faith
effort
to
fully
comply
has
been
demonstrated.
Specifically,
in
granting
deficiencies,
the
Executive
Officer
would
consider
the
following
factors:
the
extent
to
which
the
proposed
requirements
of
the
EMD
regulation
are
satisfied
overall
based
on
the
application
review,
the
relative
performance
of
the
resultant
EMD
system
compared
to
systems
fully
compliant
with
the
proposed
requirements
of
the
EMD
regulation,
and
a
demonstrated
good­
faith
effort
on
the
part
of
the
manufacturer
to:
(
1)
meet
the
proposed
requirements
in
full
by
evaluating
and
considering
the
best
available
monitoring
technology;
and
(
2)
come
into
compliance
as
expeditiously
as
possible.
The
proposed
regulation
would
have
neither
a
limit
on
the
number
of
deficiencies
granted
nor
any
fines
imposed
on
the
manufacturer
based
on
the
number
of
deficiencies
granted.

VII.
ANALYSIS
OF
ENVIRONMENTAL
IMPACTS
AND
ENVIRONMENTAL
JUSTICE
ISSUES
The
proposed
regulation
is
an
initial
step
towards
ensuring
that
forecasted
emission
reduction
benefits
from
adopted
heavy­
duty
engine
emission
standards
programs
are
achieved.
The
proposed
regulation
helps
achieve
these
emission
benefits
in
two
distinct
ways.
First,
it
is
anticipated
that
the
manufacturers
will
produce
increasingly
durable,
more
robust
emission­
related
components
to
minimize
the
detection
of
malfunctioning
components.
Second,
by
alerting
vehicle
operators
of
emission­
related
malfunctions,
repairs
can
be
made
more
promptly
to
restore
the
system
to
proper
operation.

Given
the
substantial
shortfall
in
emission
reductions
still
needed
to
attain
the
National
and
State
Ambient
Air
Quality
Standards
and
the
difficulty
in
identifying
further
sources
of
cost­
effective
emission
reductions,
it
is
vital
that
the
emission
reductions
projected
for
the
heavy­
duty
emission
standards
programs
be
achieved.
The
proposed
EMD
regulation
is
a
necessary
first
step
towards
accomplishing
this
goal.
12
Having
identified
that
the
proposed
regulation
will
not
result
in
any
adverse
environmental
impacts
but
rather
will
help
ensure
that
measurable
emission
benefits
are
achieved
statewide,
the
regulation
should
not
adversely
impact
any
community
in
the
State,
especially
low­
income
and
minority
communities.

VIII.
COST
IMPACT
OF
THE
PROPOSED
REQUIREMENTS
A.
Cost
of
the
Proposed
Requirements
Manufacturers
are
currently
developing
substantially
redesigned
emission
control
systems
to
meet
the
2007
emission
standards.
Along
with
that
redesign,
manufacturers
are
adding
hardware
for
proper
control
of
the
new
emission
components.
Accordingly,
the
costs
for
the
additional
hardware
and
new
emission
controls
have
already
been
accounted
for
in
the
costs
to
comply
with
the
2007
emission
standards.
Further,
this
very
same
hardware
will
be
used
to
meet
the
proposed
EMD
system
requirements.
As
such,
the
proposed
heavy­
duty
EMD
regulation
is
not
expected
to
result
in
additional
hardware
costs
for
manufacturers.

In
regards
to
software,
manufacturers
are
also
currently
increasing
computer
memory
space
to
accommodate
the
needed
software
algorithms
for
proper
emission
control.
Given
the
limited
scope
of
the
proposed
EMD
requirements
for
fuel
system,
EGR,
and
PM
traps
and
because
the
proposed
monitoring
requirements
are
structured
around
detecting
a
fault
when
the
system
is
operating
outside
of
the
manufacturer's
control
limits,
the
cost
for
additional
software
(
if
any)
for
these
diagnostics
is
negligible.
For
the
other
emission­
related
electronic
components,
the
proposed
EMD
monitoring
requirements
are
very
similar
to
the
level
of
diagnostics
manufacturers
already
currently
implement
to
aid
service
technicians
and
to
ensure
the
engine
and
control
system
is
robust
to
failures
that
may
occur
in­
use.
As
such,
it
is
anticipated
that
there
will
be
no
additional
cost
for
software
to
meet
the
proposed
EMD
requirements.

B.
Cost
Effectiveness
of
the
Proposed
Requirements
As
stated
above,
the
proposed
EMD
regulation
is
the
initial
step
towards
ensuring
the
emission
reductions
projected
for
the
2007
heavy­
duty
emission
standards
are
achieved.
The
two
programs
complement
each
other
to
achieve
the
same
emission
reductions.
Accordingly,
the
costs
and
estimated
emission
reductions
for
the
EMD
proposal
are
combined
with
the
2007
emission
standards
to
determine
the
cost
effectiveness.
Given
that
the
proposed
EMD
requirements
are
not
expected
to
result
in
increased
hardware
or
software
costs
and
are
helping
to
protect
the
emission
benefits
already
projected,
the
cost
effectiveness
calculation
does
not
change
from
the
previously
calculated
value
for
the
2007
emission
standards.
For
reference,
the
2007
emission
standards
were
calculated
to
have
a
cost­
effectiveness
of
$
0.42
per
pound
of
NOx
plus
non­
methane
hydrocarbon
and
$
3.42
per
pound
of
PM
for
all
heavy­
duty
vehicles.
2
2
ARB
Staff
Report:
Initial
Statement
of
Reasons,
"
Public
Hearing
to
Consider
Amendments
Adopting
More
Stringent
Emission
Standards
for
2007
and
Subsequent
Model
Year
New
Heavy­
Duty
13
IX.
ECONOMIC
IMPACT
ANALYSIS
Overall,
the
proposed
regulation
is
expected
to
have
no
impact
on
the
profitability
of
heavy­
duty
powertrain
suppliers
(
e.
g.,
engine,
transmission).
It
is
also
anticipated
that
the
proposed
regulation
would
result
in
no
costs
to
vehicle
manufacturers.
Staff
believes,
therefore,
that
the
proposed
requirements
would
cause
no
noticeable
adverse
impact
in
California
employment,
business
status,
and
competitiveness.

A.
Legal
requirements
Sections
11346.3
of
the
Government
Code
requires
State
agencies
to
assess
the
potential
for
adverse
economic
impacts
on
California
business
enterprises
and
individuals
when
proposing
to
adopt
or
amend
any
administrative
regulation.
Section
43101
of
the
Health
and
Safety
Code
similarly
requires
that
the
Board
consider
the
impact
of
adopted
standards
on
the
California
economy.
This
assessment
shall
include
a
consideration
of
the
impact
of
the
proposed
regulation
on
California
jobs,
business
expansion,
elimination,
or
creation,
and
the
ability
of
California
business
to
compete.

In
addition,
state
agencies
are
required
to
estimate
the
cost
or
savings
to
any
state
or
local
agency,
and
school
districts.
The
estimate
is
to
include
any
nondiscretionary
cost
or
savings
to
local
agencies
and
the
cost
or
savings
in
federal
funding
to
the
state.

B.
Affected
businesses
and
potential
impacts
Any
business
involved
in
manufacturing,
purchasing,
or
servicing
heavy­
duty
engines
and
vehicles
could
be
affected
by
the
proposed
regulation.
Of
the
powertrain
businesses,
there
are
21
engine
manufacturers
and
3
transmission
and
other
powertrain
manufacturers,
none
of
which
are
located
in
California.
Of
these
businesses,
two
of
the
engine
manufacturing
companies
are
assumed
to
be
"
small
businesses"
(
i.
e.,
selling
less
than
150
engines
per
year
based
on
California
certification
data).

There
are
approximately
eight
major
vehicle
manufacturers,
but
staff
has
been
unable
to
estimate
the
total
number
of
manufacturers
that
assemble
and
sell
complete
heavy­
duty
vehicles
(
e.
g.,
coach
builders)
in
California.
Staff
has
thus
been
unable
to
determine
how
many
of
these
companies
are
located
in
California
and
how
many
are
considered
"
small
businesses."
However,
it
is
assumed
that
for
these
manufacturers,
the
regulation
would
impose
little,
if
any,
cost.

C.
Potential
impacts
on
vehicle
operators
The
proposed
regulation
would
encourage
manufacturers
to
build
more
durable
Diesel
Engines",
September
7,
2001.
14
engines,
which
would
result
in
the
need
for
fewer
repairs
and
savings
for
consumers.
Additionally,
the
proposed
EMD
regulation
is
anticipated
to
have
no
impact
on
new
vehicle
prices.

D.
Potential
impacts
on
business
competitiveness
The
proposed
regulation
is
not
expected
to
adversely
impact
the
ability
of
California
businesses
to
compete
with
businesses
in
other
states
as
the
proposed
standards
are
anticipated
to
have
no
impact
on
retail
prices
of
new
engines
and
vehicles.
Additionally,
the
U.
S.
EPA
is
expected
to
adopt
federal
heavy­
duty
requirements
that
are
harmonized
with
those
of
ARB.
Accordingly,
even
if
there
were
a
price
increase
for
heavy­
duty
vehicles,
it
would
not
be
expected
to
dampen
the
demand
for
heavy­
duty
trucks
in
California
relative
to
other
states,
since
any
such
price
increase
would
be
the
same
nationwide.

Further,
all
manufacturers
that
manufacture
heavy­
duty
engines
or
powertrain
components
for
sale
in
California
are
subject
to
the
proposed
heavy­
duty
EMD
requirements
regardless
of
where
they
are
located
and
where
the
engines
are
planned
for
sale.
As
stated
above,
none
of
the
heavy­
duty
engine
or
powertrain
manufacturers
are
located
in
California.

E.
Potential
impact
on
employment
The
proposed
regulation
is
not
expected
to
cause
a
noticeable
change
in
California
employment
because
California
accounts
for
only
a
small
share
of
engine
and
powertrain
manufacturing
employment,
and
the
minimal
additional
work
done
by
vehicle
manufacturers
can
be
done
with
existing
staff.

F.
Potential
impact
on
business
creation,
elimination,
or
expansion
The
proposed
regulation
is
not
expected
to
affect
business
creation,
elimination,
or
expansion.
15
REFERENCES
Below
is
a
list
of
documents
and
other
information
that
the
ARB
staff
relied
upon
in
proposing
the
heavy­
duty
EMD
regulation.

Salvat,
O.,
Marez,
P.,
and
Belot,
G.,
"
Passenger
Car
Serial
Application
of
a
Particulate
Filter
System
on
a
Common
Rail
Direct
Injection
Diesel
Engine,"
SAE
Paper
2000­
01­
0473.3
ARB
Staff
Report:
Initial
Statement
of
Reasons,
"
Public
Hearing
to
Consider
Amendments
Adopting
More
Stringent
Emission
Standards
for
2007
and
Subsequent
Model
Year
New
Heavy­
Duty
Diesel
Engines",
September
7,
2001.
http://
www.
arb.
ca.
gov/
regact/
HDDE2007/
hdde2007.
htm
3
Copies
of
Society
of
Automotive
Engineers
(
SAE)
papers
are
available
through
the
SAE
at:
SAE
Customer
Service
400
Commonwealth
Drive
Warrendale,
PA
15096­
0001,
U.
S.
A.
Phone:
1­
877­
606­
7323
(
U.
S.
and
Canada
only)
724­
776­
4970
(
outside
U.
S.
and
Canada)
Fax:
724­
776­
0790
E­
mail:
CustomerService@
sae.
org
Website:
http://
www.
sae.
org
