2005 MERCEDES-BENZ SPRINTER brake fluid

The TCM continuously checks for electrical prob-
lems, mechanical problems, and some hydraulic prob-
lems. When a problem is sensed, the TCM stores a
diagnostic trouble code (DTC). Some of these codes
cause the transmission to go into9Limp-In9or
9default9mode. Some DTCs cause permanent
Limp-In and others cause temporary Limp-In. The
NAG1 defaults in the current gear position if a DTC
is detected, then after a key cycle the transmission
will go into Limp-in, which is mechanical 2nd gear.
Some DTCs may allow the transmission to resume
normal operation (recover) if the detected problem
goes away. A permanent Limp-In DTC will recover
when the key is cycled, but if the same DTC is
detected for three key cycles the system will not
recover and the DTC must be cleared from the TCM
with the DRBIIItscan tool.
TCM SIGNALS
The TCM registers one part of the input signals by
direct inputs, the other part by CAN C bus. In addi-
tion to the direct control of the actuators, the TCM
sends various output signals by CAN C bus to other
control modules.
Selector Lever Position
The TCM monitors the SLA for all shift lever posi-
tions via the CAN bus.
ATF Temperature Sensor
The ATF temperature sensor is a positive temper-
ature co-efficient (PTC) thermistor. It measures the
temperature of the transmission fluid and is a direct
input signal for the TCM. The temperature of the
ATF has an influence on the shifttime and resulting
shift quality. As the temperature rises, resistance
rises, and therefore, the probing voltage is decreas-
ing. Because of its registration, the shifting process
can be optimized in all temperature ranges.
The ATF temperature sensor is wired in series
with the park/neutral contact. The temperature sig-
nal is transmitted to the TCM only when the reed
contact of the park/neutral contact is closed because
the TCM only reads ATF temperature while in any
forward gear, or REVERSE. When the transmission
is in PARK or NEUTRAL, the TCM will substitute
the engine temperature for the ATF temperature.
Starter Interlock
The TCM monitors a contact switch wired in series
with the transmission temperature sensor to deter-
mine PARK and NEUTRAL positions. The contact
switch is open in PARK and NEUTRAL. The TCM
senses transmission temperature as high (switch
supply voltage), confirming switch status as open.
The TCM then broadcasts a message over CAN bus
to confirm switch status. The PCM receives thisinformation and allows operation of the starter cir-
cuit.
N2 and N3 Speed Sensors
The N2 and N3 Input Speed Sensors are two Hall-
effect speed sensors that are mounted internally in
the transmission and are used by the TCM to calcu-
late the transmission's input speed. Since the input
speed cannot be measured directly, two of the drive
elements are measured. Two input speed sensors
were required because both drive elements are not
active in all gears.
CAN C Bus Indirect Input Signals
A 2.5-volt bias (operating voltage) is present on the
CAN C bus any time the ignition switch is in the
RUN position. Both the TCM and the ABS apply this
bias. On this vehicle, the CAN C bus is used for mod-
ule data exchange only. The indirect inputs used on
the NAG1 electronic control system are:
²Wheel Speed Sensors.
²Brake Switch.
²Engine RPM.
²Engine Temperature.
²Cruise Control Status.
²Gear Limit Request.
²Throttle Position - 0% at idle, 100% at WOT. If
open, TCM assumes idle (0% throttle opening).
²Odometer Mileage
²Maximum Effective Torque.
²Engine in Limp-In Mode/Mileage Where DTC
Was Set.
BRAKE TRANSMISSION SHIFT INTERLOCK (BTSI)
The BTSI solenoid prevents shifting out of the
PARK position until the ignition key is in the RUN
position and the brake pedal is pressed. The TCM
controls the ground while the ignition switch supplies
power to the BTSI solenoid. The PCM monitors the
brake switch and broadcasts brake switch status
messages over the CAN C bus. If the park brake is
depressed and there is power (Run/Start) to SLA, the
BTSI solenoid deactivates.
SHIFT SCHEDULES
The basic shift schedule includes up and down-
shifts for all five gears. The TCM adapts the shift
program according to driving style, accelerator pedal
position and deviation of vehicle speed. Influencing
factors are:
²Road Conditions.
²Incline, Decline and Altitude.
²Trailer Operation, Loading.
²Engine Coolant Temperature.
²Cruise Control Operation.
²Sporty Driving Style.
8E - 6 ELECTRONIC CONTROL MODULESVA
TRANSMISSION CONTROL MODULE (Continued)

INSTRUMENT CLUSTER
TABLE OF CONTENTS
page page
INSTRUMENT CLUSTER
DESCRIPTION..........................2
OPERATION............................5
DIAGNOSIS AND TESTING - INSTRUMENT
CLUSTER............................7
REMOVAL.............................7
INSTALLATION..........................9
ABS INDICATOR
DESCRIPTION..........................9
OPERATION............................9
AIRBAG INDICATOR
DESCRIPTION.........................10
OPERATION...........................10
AMBIENT TEMPERATURE INDICATOR
DESCRIPTION.........................11
OPERATION...........................11
BRAKE/PARK BRAKE INDICATOR
DESCRIPTION.........................11
OPERATION...........................12
BRAKE WEAR INDICATOR
DESCRIPTION.........................12
OPERATION...........................12
CHARGING INDICATOR
DESCRIPTION.........................13
OPERATION...........................13
CLOCK
DESCRIPTION.........................13
OPERATION...........................14
COOLANT LOW INDICATOR
DESCRIPTION.........................14
OPERATION...........................14
ENGINE TEMPERATURE GAUGE
DESCRIPTION.........................15
OPERATION...........................15
FUEL FILTER CLOGGED INDICATOR
DESCRIPTION.........................15
OPERATION...........................15
FUEL GAUGE
DESCRIPTION.........................16
OPERATION...........................16
GEAR SELECTOR INDICATOR
DESCRIPTION.........................17
OPERATION...........................17
HIGH BEAM INDICATOR
DESCRIPTION.........................17
OPERATION...........................17LOW FUEL INDICATOR
DESCRIPTION.........................18
OPERATION...........................18
LOW OIL LEVEL INDICATOR
DESCRIPTION.........................18
OPERATION...........................18
MAINTENANCE INDICATOR
DESCRIPTION.........................19
OPERATION...........................19
MALFUNCTION INDICATOR LAMP (MIL)
DESCRIPTION.........................20
OPERATION...........................20
MULTI-FUNCTION INDICATOR
DESCRIPTION.........................20
OPERATION...........................21
ODOMETER
DESCRIPTION.........................21
OPERATION...........................22
SEATBELT INDICATOR
DESCRIPTION.........................22
OPERATION...........................22
SPEEDOMETER
DESCRIPTION.........................23
OPERATION...........................23
TACHOMETER
DESCRIPTION.........................23
OPERATION...........................24
TRACTION CONTROL INDICATOR
DESCRIPTION.........................24
OPERATION...........................24
TRACTION CONTROL MALFUNCTION
INDICATOR
DESCRIPTION.........................25
OPERATION...........................25
TURN SIGNAL INDICATOR
DESCRIPTION.........................25
OPERATION...........................25
WAIT-TO-START INDICATOR
DESCRIPTION.........................26
OPERATION...........................26
WASHER FLUID INDICATOR
DESCRIPTION.........................27
OPERATION...........................27
WATER-IN-FUEL INDICATOR
DESCRIPTION.........................27
OPERATION...........................28
VAINSTRUMENT CLUSTER 8J - 1

arate take out and connector of the vehicle wire
harness.
Located between the rear cover and the cluster
hood is the cluster housing. The molded plastic clus-
ter housing serves as the carrier for the cluster elec-
tronic circuit board and circuitry, the cluster
connector receptacles, the gauges, a Light Emitting
Diode (LED) for each cluster indicator and general
illumination lamp, the multi-function indicator LCD
unit, electronic tone generators, the cluster overlay,
the gauge pointers, the multi-function indicator
switches and the four switch push buttons.
The cluster overlay is a laminated plastic unit. The
dark, visible, outer surface of the overlay is marked
with all of the gauge dial faces and graduations, but
this layer is also translucent. The darkness of this
outer layer prevents the cluster from appearing clut-
tered or busy by concealing the cluster indicators
that are not illuminated, while the translucence of
this layer allows those indicators and icons that are
illuminated to be readily visible. The underlying
layer of the overlay is opaque and allows light from
the LED for each of the various indicators and illu-
mination lamps behind it to be visible through the
outer layer of the overlay only through predeter-
mined cutouts. A rectangular opening in the overlay
at the base of the speedometer provides a window
through which the illuminated multi-function indica-
tor LCD unit can be viewed.
Several versions of the EMIC module are offered
on this model. These versions accommodate all of the
variations of optional equipment and regulatory
requirements for the various markets in which the
vehicle will be offered. The microprocessor-based
EMIC utilizes integrated circuitry, Electrically Eras-
able Programmable Read Only Memory (EEPROM)
type memory storage, information carried on the
Controller Area Network (CAN) data bus, along with
several hard wired analog and multiplexed inputs to
monitor systems, sensors and switches throughout
the vehicle.
In response to those inputs, the hardware and soft-
ware of the EMIC allow it to control and integrate
many electronic functions and features of the vehicle
through both hard wired outputs and the transmis-
sion of electronic message outputs to other electronic
modules in the vehicle over the CAN data bus. (Refer
to 8 - ELECTRICAL/ELECTRONIC CONTROL
MODULES/COMMUNICATION - DESCRIPTION -
CAN BUS).
Besides typical instrument cluster gauge and indi-
cator support, the electronic functions and features
that the EMIC supports or controls include the fol-
lowing:
²Active Service System- In vehicles equipped
with the Active Service SYSTem (ASSYST) engine oilmaintenance indicator option, the EMIC electronic
circuit board includes a second dedicated micropro-
cessor. This second microprocessor evaluates various
data including time, mileage, and driving conditions
to calculate the required engine oil service intervals,
and provides both visual and audible alerts to the
vehicle operator when certain engine oil maintenance
services are required.
²Audible Warnings- The EMIC electronic cir-
cuit board is equipped with an audible tone generator
and programming that allows it to provide various
audible alerts to the vehicle operator, including buzz-
ing and chime tones. An audible contactless elec-
tronic relay is also soldered onto the circuit board to
produce audible clicks that is synchronized with turn
signal indicator flashing to emulate the sounds of a
conventional turn signal or hazard warning flasher.
These audible clicks can occur at one of two rates to
emulate both normal and bulb-out turn or hazard
flasher operation. (Refer to 8 - ELECTRICAL/
CHIME/BUZZER - DESCRIPTION).
²Panel Lamps Dimming Control- The EMIC
provides a hard wired 12-volt Pulse-Width Modulated
(PWM) output that synchronizes the dimming level
of all panel lamps dimmer controlled lamps with that
of the cluster general illumination lamps and multi-
function indicator.
The EMIC houses four analog gauges and has pro-
visions for up to nineteen indicators (Fig. 3). The
EMIC includes the following analog gauges:
²Coolant Temperature Gauge
²Fuel Gauge
²Speedometer
²Tachometer
The EMIC includes provisions for the following
indicators (Fig. 3):
²Airbag (SRS) Indicator
²Antilock Brake System (ABS) Indicator
²Brake Indicator
²Brake Wear Indicator
²Charging Indicator
²Clogged Fuel Filter Indicator
²Coolant Low Indicator
²High Beam Indicator
²Low Fuel Indicator
²Malfunction Indicator Lamp (MIL)
²Multi-Function Indicator (LCD)
²Seatbelt Indicator
²Traction Control (ASR) Indicator
²Traction Control (ASR) Malfunction Indica-
tor
²Turn Signal (Right and Left) Indicators
²Washer Fluid Indicator
²Wait-To-Start Indicator
²Water-In-Fuel Indicator
VAINSTRUMENT CLUSTER 8J - 3
INSTRUMENT CLUSTER (Continued)

Except for the indications provided within the
multi-function indicator LCD unit, each indicator in
the EMIC is illuminated by a dedicated LED that is
soldered onto the EMIC electronic circuit board.
Cluster illumination is accomplished by dimmable
LED back lighting, which illuminates the gauges for
visibility when the exterior lighting is turned on. The
cluster general illumination LED units are also sol-
dered onto the EMIC electronic circuit board. The
LED units are not available for service replacement
and, if damaged or faulty, the entire EMIC must be
replaced.
Hard wired circuitry connects the EMIC to the
electrical system of the vehicle. These hard wired cir-cuits are integral to the vehicle wire harnesses,
which are routed throughout the vehicle and retained
by many different methods. These circuits may be
connected to each other, to the vehicle electrical sys-
tem and to the EMIC through the use of a combina-
tion of soldered splices, splice block connectors, and
many different types of wire harness terminal con-
nectors and insulators. Refer to the appropriate wir-
ing information. The wiring information includes
wiring diagrams, proper wire and connector repair
procedures, further details on wire harness routing
and retention, as well as pin-out and location views
for the various wire harness connectors, splices and
grounds.
Fig. 3 Gauges & Indicators
1 - AIRBAG INDICATOR 14 - SEATBELT INDICATOR
2 - TACHOMETER 15 - ABS INDICATOR
3 - LEFT TURN INDICATOR 16 - MULTI-FUNCTION INDICATOR PLUS/MINUS SWITCH PUSH
BUTTONS
4 - SPEEDOMETER 17 - MULTI-FUNCTION INDICATOR (INCLUDES: CLOCK, GEAR
SELECTOR INDICATOR, ODOMETER, TRIP ODOMETER,
ENGINE OIL LEVEL DATA, AMBIENT TEMPERATURE
INDICATOR [OPTIONAL], & ACTIVE SERVICE SYSTEM
[ASSYST] ENGINE OIL MAINTENANCE INDICATOR [OPTIONAL])
5 - TRACTION CONTROL INDICATOR 18 - MULTI-FUNCTION INDICATOR MODE (MILES
[KILOMETERS]/TIME) SWITCH PUSH BUTTONS
6 - RIGHT TURN INDICATOR 19 - COOLANT LOW INDICATOR
7 - ENGINE TEMPERATURE GAUGE 20 - BRAKE INDICATOR
8 - FUEL GAUGE 21 - OIL LEVEL INDICATOR
9 - WAIT-TO-START INDICATOR 22 - BRAKE WEAR INDICATOR
10 - WASHER FLUID INDICATOR (OPTIONAL) 23 - WATER-IN-FUEL INDICATOR
11 - LOW FUEL INDICATOR 24 - CHARGING INDICATOR
12 - TRACTION CONTROL MALFUNCTION INDICATOR 25 - HIGH BEAM INDICATOR
13 - MALFUNCTION INDICATOR LAMP 26 - FUEL FILTER CLOGGED INDICATOR
8J - 4 INSTRUMENT CLUSTERVA
INSTRUMENT CLUSTER (Continued)

INDICATORS
Indicators are located in various positions within
the EMIC and are all connected to the EMIC elec-
tronic circuit board. The ambient temperature indica-
tor (optional), brake indicator, brake wear indicator,
charging indicator, coolant low indicator, high beam
indicator, low fuel indicator, seatbelt indicator, turn
signal indicators, and washer fluid indicator operate
based upon hard wired inputs to the EMIC. The air-
bag (SRS) indicator is normally controlled by a hard
wired input from the Airbag Control Module (ACM);
however, if the EMIC sees an abnormal or no input
from the ACM, it will automatically turn the airbag
indicator On until the hard wired input from the
ACM has been restored. The Malfunction Indicator
Lamp (MIL) is normally controlled by CAN data bus
messages from the Engine Control Module (ECM);
however, if the EMIC loses CAN data bus communi-
cation, the EMIC circuitry will automatically turn
the MIL on until CAN data bus communication is
restored. The EMIC uses CAN data bus messages
from the ECM, the ACM, and the Controller Antilock
Brake to control all of the remaining indicators.
The various EMIC indicators are controlled by dif-
ferent strategies; some receive battery feed from the
EMIC circuitry and have a switched ground, while
others are grounded through the EMIC circuitry and
have a switched battery feed. However, all indicators
are completely controlled by the EMIC microproces-
sor based upon various hard wired and electronic
message inputs. Except for the indications provided
by the multi-function indicator Liquid Crystal Dis-
play (LCD) unit, all indicators are illuminated at a
fixed intensity, which is not affected by the selected
illumination intensity of the EMIC general illumina-
tion lamps.
The hard wired indicator inputs may be diagnosed
using conventional diagnostic methods. However,
proper testing of the EMIC circuitry and the CAN
bus message controlled indicators requires the use of
a DRBIIItscan tool. Refer to the appropriate diag-
nostic information. Specific details of the operation
for each indicator may be found elsewhere in this
service information.
CLUSTER ILLUMINATION
The EMIC has several general illumination lamps
that are illuminated when the exterior lighting is
turned on with the multi-function switch. The illumi-
nation intensity of these lamps is adjusted by a dim-
ming level input received from the multi-function
indicator ª+º (plus) and ª±º (minus) switch push but-
tons that extend through the lower edge of the clus-
ter lens below the right end of the multi-function
indicator. When the exterior lighting is turned Off,
the display is illuminated at maximum brightness.When the exterior lighting is turned On and the
transmission gear selector is in the Park position,
depressing the plus switch push button brightens the
display lighting, and depressing the minus switch
push button dims the display lighting. The EMIC
also provides a Pulse-Width Modulated (PWM) panel
lamps dimmer output that can be used to synchro-
nize the illumination lighting levels of external illu-
mination lamps (up to about 23 to 30 watts) with
that of the EMIC.
The hard wired multi-function switch input and
the EMIC panel lamps dimmer output may be diag-
nosed using conventional diagnostic methods. How-
ever, proper testing of the PWM control of the EMIC
and the electronic dimming level inputs from the
multi-function indicator push buttons requires the
use of a DRBIIItscan tool. Refer to the appropriate
diagnostic information.
INPUT AND OUTPUT CIRCUITS
HARD WIRED INPUTS
The hard wired inputs to the EMIC include the fol-
lowing:
NOTE: Final approved circuit names were not yet
available at the time this information was compiled.
²Airbag Indicator Driver
²Ambient Temperature Sensor Signal
(Optional)
²Brake Wear Indicator Sense
²Charging Indicator Driver
²Coolant Level Switch Sense
²Front Door Jamb Switch Sense
²Fuel Level Sensor Signal
²Fused B(+)
²Fused Ignition Switch Output
²High Beam Indicator Driver
²Key-In Ignition Switch Sense
²Left Turn Signal
²Park Brake Switch Sense
²Right Turn Signal
²Seat Belt Switch Sense
²Washer Fluid Switch Sense (Optional)
Refer to the appropriate wiring information for
additional details.
HARD WIRED OUTPUTS
The hard wired outputs of the EMIC include the
following:
NOTE: Final approved circuit names were not yet
available at the time this information was compiled.
²Engine Running Relay Control
²Panel Lamps Driver
8J - 6 INSTRUMENT CLUSTERVA
INSTRUMENT CLUSTER (Continued)

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 the parking brake is applied, or
when there are certain brake hydraulic system mal-
functions as indicated by a low brake hydraulic fluid
level condition. This indicator is controlled by a tran-
sistor on the instrument cluster circuit board based
upon cluster programming and hard wired inputs
from the park brake switch and 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 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 brake indicator for the follow-
ing 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 park brake/brake
fluid level switch sense circuit (brake fluid level
switch closed = brake fluid level low) while the igni-
tion switch is in the On position, the brake indicator
is illuminated. The indicator remains illuminated
until the brake fluid level switch sense 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.
²Park Brake Switch Input- Each time the
cluster detects ground on the park brake/brake fluid
level switch sense circuit (park brake switch closed =
park brake applied or not fully released) while the
ignition switch is in the On position, the brake indi-
cator is illuminated. The indicator remains illumi-
nated until the park brake switch sense input to the
cluster is an open circuit (park brake switch open =
park brake fully released), or until the ignition
switch is turned to the Off position, whichever occurs
first.
The park brake switch on the park brake pedal
mechanism and the brake fluid level switch in the
brake master cylinder provide a hard wired ground
input to the instrument cluster circuitry through thepark brake/brake fluid level switch sense circuit
whenever the park brake is applied or not fully
released, or whenever the fluid level in the brake
master cylinder is low. The two switches are con-
nected in parallel between ground and the instru-
ment cluster. The park brake switch, brake fluid
level switch, and their input circuit to the instrument
cluster can be diagnosed using conventional diagnos-
tic tools and methods. For proper diagnosis of the
instrument cluster circuitry that controls the brake
indicator, a DRBIIItscan tool is required. Refer to
the appropriate diagnostic information.
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
8J - 12 INSTRUMENT CLUSTERVA
BRAKE/PARK BRAKE INDICATOR (Continued)

the wait-to-start indicator will be illuminated. The
indicator remains illuminated until the cluster
receives a wait-to-start lamp-off message indicating
that the pre-heat mode of the glow plugs has been
completed, until the ECM detects that the engine is
running, or until the ignition switch is turned to the
Off position, whichever occurs first.
The ECM continually monitors the engine coolant
temperature sensor to determine when the glow
plugs need to be energized in their pre-heat operat-
ing mode. The ECM then sends the proper wait-to-
start lamp-on and lamp-off messages to the
instrument cluster. If the instrument cluster turns on
the indicator after the engine is started, it may indi-
cate that a malfunction has occurred and that the
engine glow control system requires service. The
ECM will store a Diagnostic Trouble Code (DTC) for
any malfunction it detects. For proper diagnosis of
the engine coolant temperature sensor, the engine
glow control system and circuits, the ECM, the CAN
data bus, or the electronic message inputs to the
instrument cluster that control the wait-to-start indi-
cator, a DRBIIItscan tool is required. Refer to the
appropriate diagnostic information.
WASHER FLUID INDICATOR
DESCRIPTION
A washer fluid indicator is standard equipment on
all instrument clusters. However, this indicator is
only functional on vehicles equipped with an optional
washer fluid level switch integral to the washer
pump/motor unit on the washer reservoir. The
washer fluid indicator is located near the lower edge
of the instrument cluster, to the right of the multi-
function indicator display. The washer fluid indicator
consists of the International Control and Display
Symbol icon for ªWindshield Washer Fluidº 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 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 washer fluid indicator is serviced as a
unit with the instrument cluster.
OPERATION
The washer fluid indicator gives an indication to
the vehicle operator that the fluid level in the washer
reservoir is low. This indicator is controlled by theinstrument cluster circuit board based upon cluster
programming and a hard wired input from the
optional washer fluid level switch that is integral to
the washer pump/motor unit. The washer fluid indi-
cator is completely controlled by the instrument clus-
ter 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 indicator will always be off when the
ignition switch is in any position except On. The indi-
cator only illuminates when it is switched to ground
by the instrument cluster circuitry. The instrument
cluster will turn on the washer fluid indicator 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.
²Washer Fluid Level Switch Input- Each time
the cluster detects ground on the washer fluid switch
sense circuit (washer fluid level switch closed =
washer fluid level low) while the ignition switch is in
the On position, the washer fluid indicator is illumi-
nated. The indicator remains illuminated until the
washer fluid level switch input to the cluster is an
open circuit (washer fluid level switch open = washer
fluid level acceptable), or until the ignition switch is
turned to the Off position, whichever occurs first.
The instrument cluster continually monitors the
washer fluid level switch to determine the level of
the washer fluid. The instrument cluster logic applies
a delay strategy to this input to reduce the negative
effect that fluid sloshing within the reservoir can
have on reliable indicator operation. The washer
fluid level switch and circuit can be diagnosed using
conventional diagnostic tools and methods. For
proper diagnosis of the instrument cluster circuitry
that controls the washer fluid indicator, a DRBIIIt
scan tool is required. Refer to the appropriate diag-
nostic information.
WATER-IN-FUEL INDICATOR
DESCRIPTION
A water-in-fuel indicator is standard equipment in
all instrument clusters. The water-in-fuel indicator is
located near the lower edge of the instrument cluster,
to the left of the multi-function indicator display. The
water-in-fuel indicator consists of the International
Control and Display Symbol icon for ªWater In Fuelº
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
VAINSTRUMENT CLUSTER 8J - 27
WAIT-TO-START INDICATOR (Continued)

8W-02 COMPONENT INDEX
Component Page
A/C Auxiliary Fan Relay................ 8W-42
A/C Auxiliary Fan..................... 8W-42
A/C Compressor Clutch................. 8W-42
A/C Control Module-Roof................ 8W-42
A/C Fan Switch....................... 8W-42
A/C Switch-Roof...................... 8W-42
Accelerator Pedal Position Sensor......... 8W-30
Air Outlet Temperature Sensor........... 8W-42
Airbag Control Module................. 8W-43
Airbag Squibs........................ 8W-43
Ambient Temperature Sensor............ 8W-42
Ash Receiver Lamp.................... 8W-44
Automatic Temperature Control Module.... 8W-42
Auxiliary Heater Relay................. 8W-42
Auxiliary Heater Switch................ 8W-42
Battery Relay-Auxiliary................ 8W-20
Batteries............................ 8W-20
Beam Select Switch.................... 8W-50
Blower Motors........................ 8W-42
Body Plug Connector................... 8W-11
Boost Pressure Sensor.................. 8W-30
Boost Pressure Solenoid................ 8W-30
Brake Fluid Level Switch............... 8W-35
Brake Lamp Switch.................... 8W-35
Brake Wear Sensors................... 8W-35
Cabin Heater Assembly................. 8W-42
Cabin Heater Control Module............ 8W-42
Camshaft Position Sensor............... 8W-30
Center High Mounted Stop Lamp......... 8W-51
Central Timer Module.................. 8W-45
Cigar Lighter Lamp................... 8W-44
Cigar Lighter......................... 8W-41
Circulation Pump Diode................ 8W-42
Circulation Pump Relay................ 8W-42
Circulation Pump..................... 8W-42
Clockspring....................... 8W-41, 43
Contact Switch Door-Tailgate............ 8W-44
Controller Antilock Brake............... 8W-35
Courtesy Lamps...................... 8W-44
Crankcase Heater..................... 8W-30
Crankshaft Position Sensor.............. 8W-30
Ctel Antenna Connector................ 8W-55
Ctel Connector..................... 8W-47, 55
Cylinder Lock Switch-Driver............. 8W-61
D+ Relay No. 1....................... 8W-10
D+ Relay No. 2....................... 8W-11
Data Link Connector................... 8W-18
Daytime Running Lamp Relays........... 8W-50
Differential Lock Solenoid Valve.......... 8W-31
Dome Lamp.......................... 8W-44
Door Jamb Switches................... 8W-44
Door Lock Motor/Ajar Switch Assemblies . . . 8W-61Component Page
Dosing Pump......................... 8W-42
EGR Valve........................... 8W-30
Engine Control Module................. 8W-30
Engine Control Relay.................. 8W-31
Engine Coolant Level Switch............. 8W-30
Engine Coolant Temperature Sensor....... 8W-30
Engine Oil Sensor..................... 8W-30
Evaporator Temperature Sensor.......... 8W-42
Fan Stage 1 Relay..................... 8W-42
Fog Lamp Relay...................... 8W-50
Fog Lamp Switch..................... 8W-50
Fuel Injectors........................ 8W-30
Fuel Level Sensor..................... 8W-30
Fuel Pressure Sensor.................. 8W-30
Fuel Pressure Solenoid................. 8W-30
Fuel Shutdown Solenoid................ 8W-30
Fuel Temperature Sensor............... 8W-30
Fuses............................ 8W-10, 11
Fuse Blocks.......................... 8W-10
Fuse/Relay Block...................... 8W-11
Fused Ignition Switch Run-Start Relay..... 8W-11
Grounds............................ 8W-70
Generator........................... 8W-20
Glow Plug Control Module.............. 8W-30
Glow Plugs.......................... 8W-30
Hazard Warning Switch................ 8W-52
Headlamp Adjust Switch................ 8W-50
Headlamp Assemblies............... 8W-50, 52
Headlamp Switch..................... 8W-50
Heat Exchanger Connector.............. 8W-42
Heat Exchanger Switch................. 8W-42
Heated Seat Modules.................. 8W-63
Heated Seat Switches.................. 8W-63
Heater Timer-Auxiliary................. 8W-42
Hood Ajar Switch..................... 8W-39
Horn Relay.......................... 8W-41
Horn Switch......................... 8W-41
Horn............................... 8W-41
Ignition Lock Switch................... 8W-40
Ignition Switch....................... 8W-10
Instrument Cluster.................... 8W-40
Instrument Panel Socket................ 8W-40
Intake Air Temperature Sensor........... 8W-30
Interior Lamps....................... 8W-44
Interior Light Switches................. 8W-44
Interior Lighting Connector.............. 8W-44
Intrusion Sensors..................... 8W-39
Kickdown Switch...................... 8W-30
Lamp Relays......................... 8W-50
License Plate Lamps................... 8W-51
Locker Switches...................... 8W-31
Low Fuel Pressure Sensor............... 8W-30
VA8W-02 COMPONENT INDEX 8W - 02 - 1