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Light Emitting Diode (LED) behind the cutout in the
opaque layer of the overlay causes the icon to appear
silhouetted against an amber field through the trans-
lucent outer layer of the overlay when the indicator
is illuminated from behind by the LED, which is sol-
dered onto the instrument cluster electronic circuit
board. The ABS indicator is serviced as a unit with
the instrument cluster.
OPERATION
The ABS indicator gives an indication to the vehi-
cle operator when the ABS or the electronic brake
force distribution (EBV) systems are faulty or inoper-
ative. This indicator is controlled by a transistor on
the instrument cluster circuit board based upon clus-
ter programming and electronic messages received by
the cluster from the Controller Antilock Brake (CAB)
over the Controller Area Network (CAN) data bus.
The ABS indicator Light Emitting Diode (LED) is
completely controlled by the instrument cluster logic
circuit, and that logic will only allow this indicator to
operate when the instrument cluster detects that the
ignition switch is in the On position. Therefore, the
LED will always be off when the ignition switch is in
any position except On. The LED only illuminates
when it is provided a path to ground by the instru-
ment cluster transistor. The instrument cluster will
turn on the ABS indicator for the following reasons:
²Bulb Test- Each time the ignition switch is
turned to the On position the ABS indicator is illu-
minated by the cluster for about two seconds as a
bulb test.
²ABS Lamp-On Message- Each time the clus-
ter receives a lamp-on message from the CAB, the
ABS indicator will be illuminated. The indicator
remains illuminated until the cluster receives a
lamp-off message from the CAB, or until the ignition
switch is turned to the Off position, whichever occurs
first.
The CAB continually monitors the ABS and EBV
circuits and sensors to decide whether the systems
are in good operating condition. The CAB then sends
the proper lamp-on or lamp-off messages to the
instrument cluster. If the CAB sends a lamp-on mes-
sage after the bulb test, it indicates that the CAB
has detected a system malfunction and/or that the
ABS or EBV systems have become inoperative. The
CAB will store a Diagnostic Trouble Code (DTC) for
any malfunction it detects. For proper diagnosis of
the ABS and EBV systems, the CAB, the CAN data
bus, the electronic message inputs to the instrument
cluster, or the instrument cluster circuitry that con-
trols the ABS indicator, a diagnostic scan tool is
required. Refer to the appropriate diagnostic infor-
mation.
ADR INDICATOR
DESCRIPTION
A constant engine speed (ADR) indicator is stan-
dard equipment on all instrument clusters, but is
only functional on vehicles equipped with the
optional ADR switch. The ADR indicator is located
near the lower edge of the instrument cluster, to the
right of the multi-function indicator display. The
ADR indicator consists of the text ªADRº imprinted
within a rectangular cutout in the opaque layer of
the instrument cluster overlay. The dark outer layer
of the overlay prevents the indicator from being
clearly visible when it is not illuminated. An amber
Light Emitting Diode (LED) behind the cutout in the
opaque layer of the overlay causes the text to appear
silhouetted against an amber field through the trans-
lucent outer layer of the overlay when the indicator
is illuminated from behind by the LED, which is sol-
dered onto the instrument cluster electronic circuit
board. The ADR indicator is serviced as a unit with
the instrument cluster.
OPERATION
The constant engine speed (ADR) indicator gives
an indication to the vehicle operator concerning the
operating status of the constant engine speed (ADR)
feature. The ADR indicator is controlled by a transis-
tor on the instrument cluster circuit board based
upon cluster programming and electronic messages
received by the cluster from the Engine Control Mod-
ule (ECM) over the Controller Area Network (CAN)
data bus. The ADR indicator Light Emitting Diode
(LED) is completely controlled by the instrument
cluster logic circuit, and that logic will only allow
this indicator to operate when the instrument cluster
detects that the ignition switch is in the On position.
Therefore, the LED will always be off when the igni-
tion switch is in any position except On. The LED
only illuminates when it is provided a path to ground
by the instrument cluster transistor. The instrument
cluster will turn on the traction control indicator for
the following reasons:
²Constant Engine Speed (ADR) Indicator
Lamp-On Message- Each time the cluster receives
an ADR indicator lamp-on message from the ECM,
the indicator will be illuminated. The indicator is
illuminated when the ADR feature has been acti-
vated with the ADR switch, and is turned off when
the ADR feature is deactivated with the ADR switch.
The ADR indicator will be extinguished if the ADR
feature is turned off because the park brake has been
released or the vehicle is in motion. The ADR indica-
tor will also be extinguished if the service brake
pedal is depressed, but the ADR feature will auto-
matically be restored and the indicator illuminated
when the brake pedal is released. The indicator
8J - 10 INSTRUMENT CLUSTERVA
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remains illuminated until the cluster receives a
lamp-off message from the ECM, or until the ignition
switch is turned to the Off position, whichever occurs
first.
The ECM continually monitors the constant engine
speed (ADR) switch and electronic messages from the
Controller Antilock Brake (CAB) concerning the sta-
tus of the four wheel speed sensors, the park brake
switch and the brake lamp switch to determine the
correct operating mode for the ADR feature. The
ECM then sends the proper lamp-on or lamp-off mes-
sages to the instrument cluster. See the owner's man-
ual in the vehicle glove box for more information on
the features, use, activation and deactivation of the
constant engine speed (ADR) feature. For proper
diagnosis of the ADR feature, the ECM, the CAB, the
CAN data bus, or the electronic message inputs to
the instrument cluster that control the ADR indica-
tor, a diagnostic scan tool is required. Refer to the
appropriate diagnostic information.
AIRBAG INDICATOR
DESCRIPTION
An airbag indicator is standard equipment on all
instrument clusters. The airbag indicator is located
near the left edge of the instrument cluster, next to
the tachometer. The airbag indicator consists of a
stencil-like cutout of the letters ªSRSº in the opaque
layer of the instrument cluster overlay. The dark
outer layer of the overlay prevents the indicator from
being clearly visible when it is not illuminated. A red
Light Emitting Diode (LED) behind the cutout in the
opaque layer of the overlay causes the ªSRSº text to
appear in red through the translucent outer layer of
the overlay when the indicator is illuminated from
behind by the LED, which is soldered onto the
instrument cluster electronic circuit board. The air-
bag indicator is serviced as a unit with the instru-
ment cluster.
OPERATION
The airbag (SRS) indicator gives an indication to
the vehicle operator when the Airbag Control Module
(ACM) has recorded a Diagnostic Trouble Code (DTC)
for a Supplemental Restraint System (SRS) circuit or
component malfunction. Such a DTC may indicate
that the SRS is faulty or inoperative. The airbag
indicator is controlled by a transistor on the instru-
ment cluster circuit board based upon cluster pro-
gramming and a hard wired input received by the
cluster from the ACM. The airbag indicator Light
Emitting Diode (LED) is completely controlled by the
instrument cluster logic circuit, and that logic will
only allow this indicator to operate when the instru-
ment cluster detects that the ignition switch is in the
On position. Therefore, the LED will always be offwhen the ignition switch is in any position except
On. The LED only illuminates when it is provided a
path to ground by the instrument cluster transistor.
The instrument cluster will turn on the airbag indi-
cator for the following reasons:
²Bulb Test- Each time the ignition switch is
turned to the On position the airbag indicator is illu-
minated for about four seconds. The entire four sec-
ond bulb test is a function of the ACM.
²Airbag Lamp-On Input- Each time the cluster
receives a lamp-on input from the ACM, the airbag
indicator will be illuminated. The indicator can be
flashed on and off, or illuminated solid, as dictated
by the ACM input. For some DTC's, if the problem
does not recur, the ACM will send a lamp-off input
automatically. Other DTC's may require that a fault
be repaired and the ACM be reset before a lamp-off
input will be sent. For more information on the ACM
and the DTC set and reset parameters, refer to 8 -
ELECTRICAL/RESTRAINTS/AIRBAG CONTROL
MODULE - OPERATION). The indicator remains
illuminated until the cluster receives a lamp-off
input from the ACM, or until the ignition switch is
turned to the Off position, whichever occurs first.
²Airbag Indicator Malfunction- Following the
seatbelt reminder function, each time the cluster
detects a malfunction in the airbag (SRS) indicator or
the airbag indicator circuit, the cluster will flash the
seatbelt indicator on and off. The cluster will con-
tinue to flash the seatbelt indicator until the airbag
indicator circuit fault is resolved, or until the ignition
switch is turned to the Off position, whichever occurs
first.
The ACM continually monitors the SRS circuits
and sensors to decide whether the system is in good
operating condition. The ACM then provides the
proper lamp-on or lamp-off inputs to the instrument
cluster. If the ACM provides a lamp-on input after
the bulb test, it indicates that the ACM has detected
a system malfunction and/or that the airbags and
seat belt tensioners may not deploy when required,
or may deploy when not required. The ACM will
store a DTC for any malfunction it detects. The ACM
input circuit to the instrument cluster can be diag-
nosed using conventional diagnostic tools and meth-
ods. For proper diagnosis of the SRS, the ACM, or
the instrument cluster circuitry that controls the air-
bag indicator, a diagnostic scan tool is required. Refer
to the appropriate diagnostic information.
AMBIENT TEMPERATURE
INDICATOR
DESCRIPTION
An ambient temperature indicator is optional
equipment on all instrument clusters. In vehicles so
VAINSTRUMENT CLUSTER 8J - 11
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equipped, the ambient temperature indication can be
toggled with the clock indication on the right side of
the multi-function indicator Liquid Crystal Display
(LCD) located near the lower edge of the instrument
cluster, directly below the speedometer. The ambient
temperature indication consists of a numeric value
with a ª+º (plus) or ª2º (minus) prefix, and the unit
of measure is identified with the characters ªÉCº
(Canadian vehicles only) or ªÉFº (United States vehi-
cles only) located directly above the temperature
indication. The indications of the ambient tempera-
ture indicator are not visible when the LCD is not
illuminated. When illuminated the indications
appear as dark characters and icons silhouetted
against an amber field. When the exterior lighting is
turned Off, the display is illuminated at maximum
brightness. When the exterior lighting is turned On
the display illumination level can be adjusted in con-
cert with the cluster general illumination lighting
using the ª+º (plus) and ª2º (minus) multi-function
indicator push buttons. The ambient temperature
indicator is serviced as a unit with the instrument
cluster.
OPERATION
The optional ambient temperature indicator gives
an indication to the vehicle operator of the outside
air temperature. This indicator is controlled by the
instrument cluster microprocessor based upon cluster
programming and a hard wired input received by the
cluster from the ambient temperature sensor. The
ambient temperature indicator is completely con-
trolled by the instrument cluster logic circuit, and
that logic will allow this indicator to operate when-
ever the multi-function indicator Liquid Crystal Dis-
play (LCD) is activated. Therefore, the ambient
temperature indicator remains functional regardless
of the ignition switch position.
The vehicle operator can choose to have the ambi-
ent temperature indicator displayed instead of the
clock information, but the clock and ambient temper-
ature indicator cannot be displayed at the same time.
The clock or ambient temperature indicator display
option is selected using the multi-function indicator
clock switch on the instrument cluster circuit board.
This switch is actuated manually by depressing the
clock switch push button that extends through the
lower edge of the cluster lens below the left end of
the multi-function indicator. Actuating this switch
momentarily will toggle the display between the
clock and ambient temperature indicator modes.
Actuating this switch twice within about one second
will cause the display to toggle, but then automati-
cally revert to the originally selected mode after
about twenty seconds.
The ambient temperature sensor located below the
front bumper is a Negative Temperature Coefficient
(NTC) thermistor. The internal resistance of the sen-sor is reduced as the ambient temperature rises. The
instrument cluster continually monitors the resis-
tance through the sensor to determine the tempera-
ture value to be displayed. The current value is
displayed immediately after the LCD is activated.
The display value will remain static regardless of
decreases in the sensor resistance (temperature ris-
ing) below vehicle speeds of 10 to 15 kilometers-per-
hour (6 to 9 miles-per-hour). Decreases in the sensor
resistance above 15 kilometers-per-hour (9 miles-per-
hour) and increases the sensor resistance (tempera-
ture falling) regardless of vehicle speed are displayed
subject to a sixty second delay.
The ambient temperature sensor is connected to
the instrument cluster in series between the ambient
temperature sensor return and sense circuits. The
ambient temperature sensor and the return and
sense circuits to the instrument cluster can be diag-
nosed using conventional diagnostic tools and meth-
ods. For proper diagnosis of the instrument cluster
circuitry that controls the ambient temperature indi-
cator, a diagnostic scan tool is required. Refer to the
appropriate diagnostic information.BRAKE INDICATOR
DESCRIPTION
A brake indicator is standard equipment on all
instrument clusters. The brake indicator is located
near the lower edge of the instrument cluster, to the
left of the multi-function indicator display. In vehi-
cles built for the United States market, the brake
indicator consists of a stencil-like cutout of the word
ªBRAKEº in the opaque layer of the instrument clus-
ter overlay. In vehicles built for the Canadian mar-
ket, the brake indicator consists of the International
Control and Display Symbol icon for ªBrake Failureº
imprinted within a rectangular cutout in the opaque
layer of the instrument cluster overlay. In either
case, the dark outer layer of the overlay prevents the
indicator from being clearly visible when it is not
illuminated. A red Light Emitting Diode (LED)
behind the cutout in the opaque layer of the overlay
causes the ªBRAKEº text to appear in red, or the
icon to appear silhouetted against a red field through
the translucent outer layer of the overlay when the
indicator is illuminated from behind by the LED,
which is soldered onto the instrument cluster elec-
tronic circuit board. The brake indicator is serviced
as a unit with the instrument cluster.
OPERATION
The brake indicator gives an indication to the vehi-
cle operator when there are certain brake hydraulic
system malfunctions as indicated by a low brake
hydraulic fluid level condition, or when there is a
problem in the electronic brake force distribution
8J - 12 INSTRUMENT CLUSTERVA
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(EBV) system. This indicator is controlled by a tran-
sistor on the instrument cluster circuit board based
upon cluster programming, electronic messages
received by the cluster from the Controller Antilock
Brake (CAB) over the Controller Area Network
(CAN) data bus, and a hard wired input from the
brake fluid level switch. The brake indicator Light
Emitting Diode (LED) is completely controlled by the
instrument cluster logic circuit, and that logic will
only allow this indicator to operate when the instru-
ment cluster detects that the ignition switch is in the
On position. Therefore, the LED will always be off
when the ignition switch is in any position except
On. The LED only illuminates when it is provided a
path to ground by the instrument cluster transistor.
The instrument cluster will turn on the brake indica-
tor for the following reasons:
²Bulb Test- Each time the ignition switch is
turned to the On position the brake indicator is illu-
minated by the instrument cluster for about two sec-
onds as a bulb test.
²Brake Fluid Level Switch Input- Each time
the cluster detects ground on the brake indicator sig-
nal circuit (brake fluid level switch closed = brake
fluid level low) while the ignition switch is in the On
position, the brake indicator is illuminated. The indi-
cator remains illuminated until the brake signal indi-
cator input to the cluster is an open circuit (brake
fluid level switch open = brake fluid level okay), or
until the ignition switch is turned to the Off position,
whichever occurs first.
²Electronic Brake Force Distribution (EBV)
Indicator Lamp-On Message- Each time the clus-
ter receives a EBV indicator lamp-on message from
the CAB, the indicator will be illuminated. The indi-
cator remains illuminated until the cluster receives a
lamp-off message from the CAB, or until the ignition
switch is turned to the Off position, whichever occurs
first.
The CAB continually monitors the EBV system cir-
cuits and sensors to decide whether the system is in
good operating condition. The CAB then sends the
proper lamp-on or lamp-off messages to the instru-
ment cluster. If the CAB sends a lamp-on message
after the bulb test, it indicates that the CAB has
detected a system malfunction and that the EBV sys-
tem has become inoperative. The CAB will store a
Diagnostic Trouble Code (DTC) for any malfunction it
detects.
The brake fluid level switch in the brake master
cylinder provides a hard wired ground input to the
instrument cluster circuitry through the brake indi-
cator signal circuit whenever the fluid level in the
brake master cylinder is low. The switch is connected
in parallel between ground and the instrument clus-
ter. The brake fluid level switch and the input circuit
to the instrument cluster can be diagnosed using con-
ventional diagnostic tools and methods. For properdiagnosis of the instrument cluster circuitry that con-
trols the brake indicator, a diagnostic scan tool is
required. Refer to the appropriate diagnostic infor-
mation.
BRAKE WEAR INDICATOR
DESCRIPTION
A brake wear indicator is standard equipment on
all instrument clusters. The brake wear indicator is
located near the lower edge of the instrument cluster,
to the left of the multi-function indicator display. The
brake wear indicator consists of the International
Control and Display Symbol icon for ªWorn Brake
Liningsº imprinted within a rectangular cutout in the
opaque layer of the instrument cluster overlay. The
dark outer layer of the overlay prevents the indicator
from being clearly visible when it is not illuminated.
An amber Light Emitting Diode (LED) behind the
cutout in the opaque layer of the overlay causes the
icon to appear silhouetted against an amber field
through the translucent outer layer of the overlay
when the indicator is illuminated from behind by the
LED, which is soldered onto the instrument cluster
electronic circuit board. The brake wear indicator is
serviced as a unit with the instrument cluster.
OPERATION
The brake wear indicator gives an indication to the
vehicle operator when the brake linings have reached
their wear limits. This indicator is controlled by a
transistor on the instrument cluster circuit board
based upon cluster programming and a hard wired
input from the four brake wear sensors, one at each
wheel. The brake wear indicator Light Emitting
Diode (LED) is completely controlled by the instru-
ment cluster logic circuit, and that logic will only
allow this indicator to operate when the instrument
cluster detects that the ignition switch is in the On
position. Therefore, the LED will always be off when
the ignition switch is in any position except On. The
LED only illuminates when it is provided a path to
ground by the instrument cluster transistor. The
instrument cluster will turn on the brake wear indi-
cator for the following reasons:
²Bulb Test- Each time the ignition switch is
turned to the On position the brake wear indicator is
illuminated by the instrument cluster for about two
seconds as a bulb test.
²Brake Wear Sensor Input- Each time the
cluster detects ground on the brake wear sense cir-
cuit (brake wear sensor closed = brake lining wear
limit exceeded) while the ignition switch is in the On
position, the brake wear indicator is illuminated. The
indicator remains illuminated until the brake wear
sense input to the cluster is an open circuit (brake
wear sensor open = brake lining wear within limits),
VAINSTRUMENT CLUSTER 8J - 13
Page 933 of 2305

or until the ignition switch is turned to the Off posi-
tion, whichever occurs first.
A brake wear sensor located at each wheel provides
a hard wired ground input to the instrument cluster
circuitry through the brake wear sense circuit when-
ever the brake linings for that wheel have exceeded
their wear limits. The four normally open brake wear
sensors are connected in parallel between ground and
instrument cluster. The brake wear sensors and their
input circuit to the instrument cluster can be diag-
nosed using conventional diagnostic tools and meth-
ods. For proper diagnosis of the instrument cluster
circuitry that controls the brake wear indicator, a
diagnostic scan tool is required. Refer to the appro-
priate diagnostic information.
CHARGING INDICATOR
DESCRIPTION
A charging indicator is standard equipment on all
instrument clusters. The charging indicator is located
near the lower edge of the instrument cluster, to the
left of the multi-function indicator display. The
charging indicator consists of the International Con-
trol and Display Symbol icon for ªBattery Charging
Conditionº imprinted within a rectangular cutout in
the opaque layer of the instrument cluster overlay.
The dark outer layer of the overlay prevents the indi-
cator from being clearly visible when it is not illumi-
nated. A red Light Emitting Diode (LED) behind the
cutout in the opaque layer of the overlay causes the
icon to appear silhouetted against a red field through
the translucent outer layer of the overlay when the
indicator is illuminated from behind by the LED,
which is soldered onto the instrument cluster elec-
tronic circuit board. The charging indicator is ser-
viced as a unit with the instrument cluster.
OPERATION
The charging indicator gives an indication to the
vehicle operator when the electrical system voltage is
too low. This indicator is controlled by a transistor on
the instrument cluster circuit board based upon clus-
ter programming and a hard wired input from the
generator. The charging indicator Light Emitting
Diode (LED) is completely controlled by the instru-
ment cluster logic circuit, and that logic will only
allow this indicator to operate when the instrument
cluster detects that the ignition switch is in the On
position. Therefore, the LED will always be off when
the ignition switch is in any position except On. The
LED only illuminates when it is provided a path to
ground by the instrument cluster transistor. The
instrument cluster will turn on the charging indica-
tor for the following reasons:
²Bulb Test- Each time the ignition switch is
turned to the On position with the engine not run-ning the charging indicator is illuminated by the
instrument cluster as a bulb test.
²Generator Input- Each time the cluster
detects that the voltage of the generator input is 12.7
volts or lower while the engine is running, the charg-
ing indicator will be illuminated. The indicator
remains illuminated until the cluster detects that the
voltage of the generator input is above 12.7 volts, or
until the ignition switch is turned to the Off position,
whichever occurs first.
The generator provides a hard wired input to the
instrument cluster circuitry on the engine running
(D+) circuit. If the instrument cluster turns on the
indicator while the engine is running, it may indicate
that the charging system requires service. The gener-
ator input circuit to the instrument cluster can be
diagnosed using conventional diagnostic tools and
methods. For proper diagnosis of the charging sys-
tem, or the instrument cluster circuitry that controls
the charging indicator, a diagnostic scan tool is
required. Refer to the appropriate diagnostic infor-
mation.
CLOCK
DESCRIPTION
An electronic digital clock is standard equipment
on all instrument clusters. In vehicles equipped with
the optional ambient temperature indicator, the clock
indication can be toggled with the ambient tempera-
ture indication on the right side of the multi-function
indicator Liquid Crystal Display (LCD) located near
the lower edge of the instrument cluster, directly
below the speedometer. The clock provides a 12 hour-
based, digital indication of the current hours and
minutes. The indications of the clock are not visible
when the LCD is not illuminated. When illuminated
the indications appear as dark characters silhouetted
against an amber field. When the exterior lighting is
turned Off, the display is illuminated at maximum
brightness. When the exterior lighting is turned On
the display illumination level can be adjusted in con-
cert with the cluster general illumination lighting
using the ª+º (plus) and ª2º (minus) multi-function
indicator push buttons. The clock is serviced as a
unit with the instrument cluster.
OPERATION
The clock gives an indication to the vehicle opera-
tor of the current time. The electronic digital clock is
controlled by the instrument cluster microprocessor
based upon cluster programming. The clock display is
completely controlled by the instrument cluster logic
circuit, and that logic will only allow this indication
to be viewed when the multi-function indicator Liq-
uid Crystal Display (LCD) is activated. However, the
8J - 14 INSTRUMENT CLUSTERVA
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clock remains functional regardless of the ignition
switch position.
The vehicle operator can choose to have the
optional ambient temperature indicator displayed
instead of the clock information, but the clock and
ambient temperature indicator cannot be displayed
at the same time. The clock or ambient temperature
indicator display option is selected using the multi-
function indicator clock switch on the instrument
cluster circuit board. This switch is actuated manu-
ally by depressing the clock switch push button that
extends through the lower edge of the cluster lens
below the left end of the multi-function indicator.
Actuating this switch momentarily will toggle the
display between the clock and ambient temperature
indicator modes. Actuating this switch twice within
about one second will cause the display to toggle, but
then automatically revert to the originally selected
mode after about twenty seconds.
See the owner's manual in the vehicle glove box for
more information on the features, use, operation and
setting procedures for the clock. For proper testing of
the instrument cluster circuitry that controls the
clock functions, a diagnostic scan tool is required.
Refer to the appropriate diagnostic information.
COOLANT LOW INDICATOR
DESCRIPTION
A coolant low indicator is standard equipment on
all instrument clusters. The coolant low indicator is
located near the lower edge of the instrument cluster,
to the left of the multi-function indicator display. The
coolant low indicator consists of the International
Control and Display Symbol icon for ªLow Engine
Coolantº imprinted within a rectangular cutout in
the opaque layer of the instrument cluster overlay.
The dark outer layer of the overlay prevents the indi-
cator from being clearly visible when it is not illumi-
nated. A red Light Emitting Diode (LED) behind the
cutout in the opaque layer of the overlay causes the
icon to appear silhouetted against a red field through
the translucent outer layer of the overlay when the
indicator is illuminated from behind by the LED,
which is soldered onto the instrument cluster elec-
tronic circuit board. The coolant low indicator is ser-
viced as a unit with the instrument cluster.
OPERATION
The coolant low indicator gives an indication to the
vehicle operator when the engine coolant level is low.
This indicator is controlled by a transistor on the
instrument cluster circuit board based upon cluster
programming and a hard wired input received by the
cluster from the engine coolant level switch. The cool-
ant low indicator Light Emitting Diode (LED) is com-
pletely controlled by the instrument cluster logiccircuit, and that logic will only allow this indicator to
operate when the instrument cluster detects that the
ignition switch is in the On position. Therefore, the
LED will always be off when the ignition switch is in
any position except On. The LED only illuminates
when it is provided a path to ground by the instru-
ment cluster transistor. The instrument cluster will
turn on the coolant low indicator for the following
reasons:
²Bulb Test- Each time the ignition switch is
turned to the On position the coolant low indicator is
illuminated for about two seconds as a bulb test.
²Engine Coolant Level Switch Input- Each
time the cluster detects an appropriate input on the
low coolant fluid level sense circuit (engine coolant
level switch resistance low = engine coolant level low)
while the ignition switch is in the On position, the
coolant low indicator will be illuminated. The indica-
tor remains illuminated until the low coolant fluid
level sense input to the cluster changes (engine cool-
ant level switch resistance high = engine coolant
level full), or until the ignition switch is turned to
the Off position, whichever occurs first. The engine
coolant level switch also features a diagnostic resis-
tor connected in parallel between the switch input
and output to provide the cluster with verification
that the low coolant fluid level sense circuit is not
open or shorted.
The engine coolant level switch integral to the cool-
ant bottle provides a hard wired input to the instru-
ment cluster circuitry through the low coolant fluid
level sense circuit. The engine coolant level switch
and the low coolant fluid level sense circuit to the
instrument cluster can be diagnosed using conven-
tional diagnostic tools and methods. For proper diag-
nosis of the instrument cluster circuitry that controls
the coolant low indicator, a diagnostic scan tool is
required. Refer to the appropriate diagnostic infor-
mation.
ENGINE TEMPERATURE
GAUGE
DESCRIPTION
An engine coolant temperature gauge is standard
equipment on all instrument clusters. The engine
coolant temperature gauge is located in the upper
right corner of the instrument cluster, to the right of
the speedometer. The engine coolant temperature
gauge consists of a movable gauge needle or pointer
controlled by the instrument cluster circuitry and a
fixed 45 degree scale on the cluster overlay that
reads left-to-right from 120É C to 40É C for Canadian
vehicles, or from 250É F to 110É F for United States
vehicles. An International Control and Display Sym-
bol icon for ªEngine Coolant Temperatureº is located
VAINSTRUMENT CLUSTER 8J - 15
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on the cluster overlay, directly below the high end of
the scale. Just to the right of the icon, the nomencla-
ture ªÉCº or ªÉFº confirms the unit of measure for the
gauge readings.
The engine coolant temperature gauge graphics are
white against a black field, except for a single red
graduation at the far left (high) end of the gauge
scale, making them clearly visible within the instru-
ment cluster in daylight. When illuminated from
behind by the panel lamps dimmer controlled cluster
illumination lighting with the exterior lamps turned
On, the white graphics appear amber and the red
graphics appear red. The orange gauge needle is
internally illuminated. Gauge illumination is pro-
vided by Light Emitting Diode (LED) units soldered
onto the instrument cluster electronic circuit board.
The engine coolant temperature gauge is serviced as
a unit with the instrument cluster.
OPERATION
The engine coolant temperature gauge gives an
indication to the vehicle operator of the engine cool-
ant temperature. This gauge is controlled by the
instrument cluster circuit board based upon cluster
programming and electronic messages received by
the cluster from the Engine Control Module (ECM)
over the Controller Area Network (CAN) data bus.
The engine coolant temperature gauge is an air core
magnetic unit that receives battery current on the
instrument cluster electronic circuit board when the
instrument cluster detects that the ignition switch is
in the On position. The cluster is programmed to
move the gauge needle back to the low end of the
scale after the ignition switch is turned to the Off
position. The instrument cluster circuitry controls
the gauge needle position and provides the following
features:
²Engine Temperature Normal Message- Each
time the cluster receives a message from the ECM
indicating the engine coolant temperature is within
the normal operating range [up to about 120É C (250É
F), the gauge needle is moved to the actual relative
temperature position on the gauge scale.
²Engine Temperature High Message- Each
time the cluster receives a message from the ECM
indicating the engine coolant temperature is high
[above about 120É C (250É F) the gauge needle is
moved into the red warning zone on the gauge scale.
The ECM continually monitors the engine coolant
temperature sensor to determine the engine operat-
ing temperature. The ECM then sends the proper
engine coolant temperature messages to the instru-
ment cluster. If the instrument cluster moves the
engine coolant temperature gauge needle to red area
of the gauge scale, it may indicate that the engine or
the engine cooling system require service. For proper
diagnosis of the engine coolant temperature sensor,
the ECM, the CAN data bus, the electronic messageinputs to the instrument cluster, or the instrument
cluster circuitry that controls the engine coolant tem-
perature gauge, a diagnostic scan tool is required.
Refer to the appropriate diagnostic information.
ESP INDICATOR
DESCRIPTION
An Electronic Stability Program (ESP) indicator is
standard equipment on all instrument clusters, but is
only functional on vehicles equipped with the
optional ESP system. The ESP indicator is located
near the lower edge of the instrument cluster, to the
right of the multi-function indicator display. The ESP
indicator consists of a stencil-like cutout of the text
ªESPº in the opaque layer of the instrument cluster
overlay. The dark outer layer of the overlay prevents
the indicator from being clearly visible when it is not
illuminated. An amber Light Emitting Diode (LED)
behind the cutout in the opaque layer of the overlay
causes the text to appear in amber through the
translucent outer layer of the overlay when the indi-
cator is illuminated from behind by the LED, which
is soldered onto the instrument cluster electronic cir-
cuit board. The ESP indicator is serviced as a unit
with the instrument cluster.
OPERATION
The ESP indicator gives an indication to the vehi-
cle operator when the ESP system is faulty or inop-
erative. This indicator is controlled by a transistor on
the instrument cluster circuit board based upon clus-
ter programming and electronic messages received by
the cluster from the Controller Antilock Brake (CAB)
over the Controller Area Network (CAN) data bus.
The ESP indicator Light Emitting Diode (LED) is
completely controlled by the instrument cluster logic
circuit, and that logic will only allow this indicator to
operate when the instrument cluster detects that the
ignition switch is in the On position. Therefore, the
LED will always be off when the ignition switch is in
any position except On. The LED only illuminates
when it is provided a path to ground by the instru-
ment cluster transistor. The instrument cluster will
turn on the ESP indicator for the following reasons:
²Bulb Test- Each time the ignition switch is
turned to the On position the ESP indicator is illu-
minated by the cluster for about two seconds as a
bulb test.
²ESP Lamp-On Message- Each time the clus-
ter receives a lamp-on message from the CAB, the
ESP indicator will be illuminated. The indicator
remains illuminated until the cluster receives a
lamp-off message from the CAB, or until the ignition
switch is turned to the Off position, whichever occurs
first.
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The CAB continually monitors the ESP circuits
and sensors to decide whether the system is in good
operating condition. The CAB then sends the proper
lamp-on or lamp-off messages to the instrument clus-
ter. If the CAB sends a lamp-on message after the
bulb test, it indicates that the CAB has detected a
system malfunction and/or that the ESP system has
become inoperative. The CAB will store a Diagnostic
Trouble Code (DTC) for any malfunction it detects.
For proper diagnosis of the ESP system, the CAB,
the CAN data bus, the electronic message inputs to
the instrument cluster, or the instrument cluster cir-
cuitry that controls the ESP indicator, a diagnostic
scan tool is required. Refer to the appropriate diag-
nostic information.
FUEL FILTER CLOGGED INDI-
CATOR
DESCRIPTION
A fuel filter clogged indicator is standard equip-
ment on all instrument clusters. The fuel filter
clogged indicator is located near the left edge of the
instrument cluster, next to the tachometer. The fuel
filter clogged indicator consists of the International
Control and Display Symbol icon for ªFuel Filterº
imprinted within a rectangular cutout in the opaque
layer of the instrument cluster overlay. The dark
outer layer of the overlay prevents the indicator from
being clearly visible when it is not illuminated. An
amber Light Emitting Diode (LED) behind the cutout
in the opaque layer of the overlay causes the icon to
appear silhouetted against an amber field through
the translucent outer layer of the overlay when the
indicator is illuminated from behind by the LED,
which is soldered onto the instrument cluster elec-
tronic circuit board. The fuel filter clogged indicator
is serviced as a unit with the instrument cluster.
OPERATION
The fuel filter clogged indicator gives an indication
to the vehicle operator when the pressure in the fuel
system is low, which could indicate that the fuel filter
is clogged. This indicator is controlled by a transistor
on the instrument cluster circuit board based upon
cluster programming and electronic messages
received by the cluster from the Engine Control Mod-
ule (ECM) over the Controller Area Network (CAN)
data bus. The fuel filter clogged indicator Light Emit-
ting Diode (LED) is completely controlled by the
instrument cluster logic circuit, and that logic will
only allow this indicator to operate when the instru-
ment cluster detects that the ignition switch is in the
On position. Therefore, the LED will always be off
when the ignition switch is in any position except
On. The LED only illuminates when it is provided apath to ground by the instrument cluster transistor.
The instrument cluster will turn on the fuel filter
clogged indicator for the following reasons:
²Bulb Test- Each time the ignition switch is
turned to the On position the fuel filter clogged indi-
cator is illuminated by the cluster for about two sec-
onds as a bulb test.
²Fuel Filter Clogged Lamp-On Message-
Each time the cluster receives a lamp-on message
from the ECM, the fuel filter clogged indicator will
be illuminated. The indicator remains illuminated
until the cluster receives a lamp-off message from
the ECM, or until the ignition switch is turned to the
Off position, whichever occurs first.
The ECM continually monitors the low fuel pres-
sure sensor located at the inlet of the high pressure
fuel pump to decide whether the fuel system is in
good operating condition. The ECM then sends the
proper lamp-on or lamp-off messages to the instru-
ment cluster. If the ECM sends a lamp-on message
after the bulb test, it indicates that the ECM has
detected a low pressure condition in the fuel system,
which could result from a clogged fuel filter or from
any other restrictions in the fuel delivery system.
The ECM will store a Diagnostic Trouble Code (DTC)
for any malfunction it detects. For proper diagnosis
of the low fuel pressure sensor, the ECM, the CAN
data bus, the electronic message inputs to the instru-
ment cluster, or the instrument cluster circuitry that
controls the fuel filter clogged indicator, a diagnostic
scan tool is required. Refer to the appropriate diag-
nostic information.
FUEL GAUGE
DESCRIPTION
A fuel gauge is standard equipment on all instru-
ment clusters. The fuel gauge is located in the lower
right corner of the instrument cluster, to the right of
the speedometer. The fuel gauge consists of a mov-
able gauge needle or pointer controlled by the instru-
ment cluster circuitry and a fixed 45 degree scale on
the cluster overlay that reads left-to-right from ªFº
(or Full) to ªEº (or Empty). An International Control
and Display Symbol icon for ªFuelº is located on the
cluster overlay, directly to the left of the low end of
the scale.
The fuel gauge graphics are white against a black
field, making them clearly visible within the instru-
ment cluster in daylight. When illuminated from
behind by the panel lamps dimmer controlled cluster
illumination lighting with the exterior lamps turned
On, the white graphics appear amber. The orange
gauge needle is internally illuminated. Gauge illumi-
nation is provided by Light Emitting Diode (LED)
units soldered onto the instrument cluster electronic
VAINSTRUMENT CLUSTER 8J - 17