TEMPERATURE GAUGE DIAGNOSIS
CONDITION POSSIBLE CAUSES CORRECTION
NO POINTER
MOVEMENT1. Internal Cluster Failure. 1. (a) Perform Cluster Self Diagnostic Test and check
for fault codes.
²If temperature gauge pointer moves to calibration
points during test and fault codes 110 or 111 don't
appear in the odometer display then failure is not in the
cluster. Look for another possible cause of failure.
²If the pointer doesn't move during test, go to Step
(b).
²If fault code 110 is displayed in the odometer, go to
Step (b).
²If fault code 111 is displayed in the odometer then go
to Step (f).
²If fault codes 920 or 940 are displayed refer to the
fault code chart to identify which module is causing the
fault and repair module.
(b) Replace main cluster pc board. Go to Step (c).
(c) Connect cluster into instrument panel wiring
harness. Place it back into the proper position in the
instrument panel. Put in the top two mounting screws to
hold the cluster in place. DO NOT COMPLETELY
INSTALL CLUSTER TO INSTRUMENT PANEL UNTIL
UNIT IS CALIBRATED AND TESTED. Go to Step (d).
(d) use a scan tool to calibrate cluster and perform Self
Diagnostic Test. If OK, continue installation. If not OK,
go to Step (e).
(e) Replace subdial assembly and use a scan tool to
calibrate cluster. If not OK, look at another possible
cause for the temperature gauge failure.
(f) Use a scan tool to calibrate temperature gauge and
perform Self Diagnostic Test. If OK, stop. If not OK, go
to Step (b).
2. No CCD Temperature
Message or Cold CCD
Bus Message from the
Body Control Module.2. (a) Check BCM fault codes using a scan tool. If
there are not faults, go to Step (b). If there are faults,
refer to the BCM section of the manual to properly
diagnose and repair.
(b) Check PCM fault codes using a scan tool. If there
are no faults, go to Step (c). If there are faults, refer to
the PCM section of the manual to properly diagnose
and repair.
(c) Refer to the coolant sensor section of the service
manual for the coolant sensor test procedure. Repair
sensor as needed.
NSINSTRUMENT PANEL AND SYSTEMS 8E - 11
DIAGNOSIS AND TESTING (Continued)
CONDITION POSSIBLE CAUSES CORRECTION
ERRATIC POINTER
MOVEMENT.1. Bad CCD Bus
Message from the Body
Control Module.1. (a) Check BCM fault codes using a scan tool. If
there are no faults, go to Step (b). If there are faults,
refer to the BCM section of the manual to properly
diagnose and repair.
(b) Check PCM fault codes using a scan tool. If there
are no faults, go to Step (c). If there are faults, refer to
the PCM section of the manual to properly diagnose
and repair.
(c) Refer to the coolant sensor section of the service
manual for the coolant sensor test procedure. Repair
sensor as needed.
2. Internal Cluster Failure. 2. (a) Perform Cluster Self Diagnostic Test and check
for fault codes.
²If the pointer moves during test but still appears
erratic and fault codes 110 or 111 don't appear in the
odometer display, go to Step (b).
²If fault code 110 is displayed in the odometer, go to
Step (e).
²If fault code 111 appears in the odometer display go
to Step (d).
²If fault code 920 or 940 is displayed refer to the fault
code chart to identify which mode is causing the fault
and repair module.
(b) Replace cluster subdial assembly. Go to Step (c).
(c) Connect cluster into instrument panel wiring
harness. Place it back into the proper position in the
instrument panel. DO NOT COMPLETELY INSTALL
CLUSTER TO INSTRUMENT PANEL UNTIL UNIT IS
CALIBRATED AND TESTED. Go to Step (d).
(d) Use a scan tool to calibrate cluster and perform Self
Diagnostic Test. If OK, continue installation. If not OK,
go Step (e).
(e) Replace main cluster pc board and use a scan tool
to calibrate cluster. If not OK, look at another possible
cause for the temperature gauge failure.
TEMPERATURE GAUGE
INACCURATE.1. Temperature Gauge
Out of Calibration.1. (a) Perform Cluster Self-Diagnostic Test.
²If pointer is accurate to the calibration points look for
another possible cause of failure.
²If pointer is inaccurate to the calibration points, go
the Step (b).
(b) Use a scan tool to calibrate temperature gauge.
2. Coolant Sensor Out of
Calibration.2. Refer to the Cooling section of the service manual
for test and repair procedure.
8E - 12 INSTRUMENT PANEL AND SYSTEMSNS
DIAGNOSIS AND TESTING (Continued)
CD/3-band graphic equalizer (RBR sales code), or an
AM/FM/CD/cassette/3-band graphic equalizer (RAZ
sales code).
All factory-installed radio receivers are stereo Elec-
tronically Tuned Radios (ETR) and include an elec-
tronic digital clock function.
All factory-installed radio receivers, except the
RAS model, communicate on the Chrysler Collision
Detection (CCD) data bus network through a sepa-
rate two-way wire harness connector. The CCD data
bus network allows the sharing of sensor informa-
tion. This helps to reduce wire harness complexity,
internal controller hardware, and component sensor
current loads. At the same time, this system provides
increased reliability, enhanced diagnostics, and
allows the addition of many new feature capabilities.
In addition, radios connected to the CCD data bus
have several audio system functions that can be diag-
nosed using a DRB scan tool. Refer to the proper
Diagnostic Procedures manual for more information
on DRB testing of the audio systems.
The radio can only be serviced by an authorized
radio repair station. Refer to the latest Warranty Pol-
icies and Procedures manual for a current listing of
authorized radio repair stations.
For more information on radio features, setting
procedures, and control functions refer to the owner's
manual in the vehicle glove box.
RADIO IGNITION INTERFERENCE
If receiving ignition/engine interference noise on
the radio stations, check and clean all engine and
body ground connections. Tighten properly after
cleaning. Example (Fig. 1), (Fig. 2), (Fig. 3) and (Fig.
4).
Ensure all ground connections are without corro-
sion.
CHOKEÐINFINITY SPEAKERS
If the audio system is lacking bass response, check
for continuity across the choke connector. If no conti-
nuity Replace choke. The choke is located on the
Fig. 1 Motor Mount to Frame Rail Ground
Fig. 2 2.4L Engine Block Ground
Fig. 3 3.0L Engine Block Ground
Fig. 4 3.3/3.8L Engine Block Ground
8F - 2 AUDIO SYSTEMSNS
DESCRIPTION AND OPERATION (Continued)
VEHICLE SPEED CONTROL SYSTEM
CONTENTS
page page
GENERAL INFORMATION
INTRODUCTION......................... 1
DESCRIPTION AND OPERATION
AUTOMATIC SPEED CONTROL OVERSPEED
REDUCTION........................... 2
POWERTRAIN CONTROL MODULE.......... 2
SERVO CABLE.......................... 2
SPEED CONTROL SERVO.................. 1
SPEED CONTROL SWITCHES.............. 1
STOP LAMP SWITCH..................... 2
VACUUM RESERVOIR.................... 3
VEHICLE SPEED AND DISTANCE............ 3
DIAGNOSIS AND TESTING
CHECKING FOR DIAGNOSTIC CODES........ 3
ELECTRICAL TESTS AT POWERTRAIN
CONTROL MODULE..................... 6OVERSHOOT/UNDERSHOOT FOLLOWING
SPEED CONTROL SET................... 3
ROAD TEST............................ 3
SERVO VACUUM TEST.................... 6
SPEED CONTROL ELECTRICAL TEST........ 4
SPEED CONTROL SWITCH TEST............ 6
STOP LAMP SWITCH TEST................ 6
VACUUM SUPPLY TEST................... 8
VEHICLE SPEED SENSOR................. 8
REMOVAL AND INSTALLATION
POWERTRAIN CONTROL MODULE.......... 9
SPEED CONTROL CABLE.................. 9
SPEED CONTROL SERVO.................. 8
SPEED CONTROL SWITCHES.............. 9
STOP LAMP SWITCH.................... 9
VACUUM RESEROIR..................... 10
VEHICLE SPEED SENSOR................ 10
GENERAL INFORMATION
INTRODUCTION
The speed control system is electronically con-
trolled and vacuum operated. The electronic control
is integrated into the powertrain control module,
located next to battery. The controls are located on
the steering wheel and consist of the ON/OFF, SET,
RESUME/ACCEL, CANCEL and DECEL buttons
(Fig. 1).
DESCRIPTION AND OPERATION
SPEED CONTROL SERVO
The servo unit consists of a solenoid valve body,
and a vacuum chamber. The PCM controls the sole-
noid valve body. The solenoid valve body controls the
application and release of vacuum to the diaphragm
of the vacuum servo. The servo unit cannot be
repaired and is serviced only as a complete assembly.
SPEED CONTROL SWITCHES
There are two separate switch pods that operate
the speed control system. The steering-wheel-
mounted switches use multiplexed circuits to provide
inputs to the PCM for ON, OFF, RESUME, ACCEL-
ERATE, SET, DECEL and CANCEL modes. Refer to
the owner's manual for more information on speed
control switch functions and setting procedures.
When speed control is selected by depressing the
ON switch, the PCM allows a set speed to be stored
in RAM for speed control. To store a set speed,
depress the SET switch while the vehicle is moving
at a speed between 30 and 85 mph. In order for the
speed control to engage, the brakes cannot be
applied, nor can the gear selector be indicating the
transmission is in Park or Neutral.
The speed control can be disengaged manually by:
²Stepping on the brake pedal
Fig. 1 Speed Control Switches
NSVEHICLE SPEED CONTROL SYSTEM 8H - 1
STEP IS NOT DONE A DIAGONSTIC TROUBLE
CODE (DTC) MAY BE SET.
VACUUM RESERVOIR
The reservoir contains a one-way check valve to
trap engine vacuum in the reservoir. When engine
vacuum drops, as in climbing a grade while driving,
the reservoir supplies the vacuum needed to main-
tain proper speed control operation. The vacuum res-
ervoir cannot be repaired and must be replaced if
faulty.
VEHICLE SPEED AND DISTANCE
The 4 speed automatic Transmission Control Mod-
ule (TCM) supplies the speed input to the PCM. The
PCM determines acceleration rates. The speed con-
trol software in the PCM uses vehicle speed and
acceleration to control to the set speed.
Vehicles with a 3 speed automatic or manual trans-
mission have a vehicle speed sensor (VSS) mounted
to an adapter near the transmission output shaft.
The sensor is driven through the adapter by a speed-
ometer pinion gear. The VSS pulse signal is moni-
tored by the PCM to determine vehicle speed and to
maintain speed control set speed. Refer to the appro-
priate Powertrain Diagnostic Procedures manual for
diagnosis and testing of this component. Refer to
group 14, Fuel System for Removal/Installation
DIAGNOSIS AND TESTING
ROAD TEST
Perform a vehicle road test to verify reports of
speed control system malfunction. The road test
should include attention to the speedometer. Speed-
ometer operation should be smooth and without flut-
ter at all speeds.
Flutter in the speedometer indicates a problem
which might cause surging in the speed control sys-
tem. The cause of any speedometer problems should
be corrected before proceeding. Refer to Group 8E,
Instrument Panel and Gauges for speedometer diag-
nosis.
If a road test verifies a surge following a set and
the speedometer operates properly see ªOvershoot/
Undershoot on speed control setº.
If a road test verifies an inoperative system, and
the speedometer operates properly, check for:
²A Diagnostic Trouble Code (DTC). If a DTC
exists, conduct tests per the Powertrain Diagnostic
Procedures service manual.
²A misadjusted brake (stop) lamp switch. This
could also cause an intermittent problem.
²Loose or corroded electrical connections at the
servo. Corrosion should be removed from electricalterminals and a light coating of Mopar Multipurpose
Grease, or equivalent, applied.
²Leaking vacuum reservoir.
²Loose or leaking vacuum hoses or connections.
²Defective one-way vacuum check valve.
²Secure attachment at both ends of the speed
control servo cable.
²Smooth operation of throttle linkage and throttle
body air valve.
²Conduct electrical test at PCM.
²Failed speed control servo. Do the servo vacuum
test.
CAUTION: When test probing for voltage or conti-
nuity at electrical connectors, care must be taken
not to damage connector, terminals or seals. If
these components are damaged, intermittent or
complete system failure may occur.
OVERSHOOT/UNDERSHOOT FOLLOWING SPEED
CONTROL SET
If the operator repeatedly presses and releases the
set button with their foot off of the accelerator (a ªlift
foot setº to begin speed control operation), the vehicle
may accelerate and exceed the desired set speed by
up to 5 MPH (8 km/h) and then decelerate to less
than the desired set speed before finally achieving
the desired set speed.
The Speed Control has an adaptive strategy that
compensates for vehicle-to-vehicle variations in speed
control cable lengths. When the speed control is set
with the vehicle operators foot off of the accelerator
pedal, the speed control thinks there is excessive
speed control cable slack and adapts. If the lift foot
sets are continually used, the speed control over-
shoot/undershoot condition will develop.
To ªunlearnº the overshoot/undershoot condition,
the vehicle operator has to press and release the set
button while maintaining the desired set speed with
the accelerator pedal (not decelerating or accelerat-
ing), and then turn the cruise control switch to the
OFF position (or press the CANCEL button if
equipped) after waiting 10 seconds. This procedure
must be performed approximately 10±15 times to
completely unlearn the overshoot/undershoot condi-
tion.
CHECKING FOR DIAGNOSTIC CODES
When trying to verify a speed control system elec-
tronic malfunction: Connect a DRB scan tool if avail-
able to the data link connector. The connector is
located at left side of the steering column, and at
lower edge of the panel.
(1) A speed control malfunction may occur without
a diagnostic code being indicated.
NSVEHICLE SPEED CONTROL SYSTEM 8H - 3
DESCRIPTION AND OPERATION (Continued)
Refer to Group 25, for further information and use-
age of the DRB scan tool and a more complete list of
Diagnostic Trouble Code.
SPEED CONTROL SLOWS DOWN BY ITSELF
Test vehicle speed sensor, refer to group 8E. If sen-
sor fails replace sensor, if it passes perform the fol-
lowing test:
(1) Perform the speed control switch test on the
DECEL switch, if it fails replace switch.
(2) If the switch passes, conduct the vacuum sup-
ply test.
(3) If it passes, conduct the servo vacuum test. If it
fails replace servo.
(4) If continuity, replace the PCM.
SPEED CONTROL ELECTRICAL TEST
Electronic speed control systems may be tested
using two different methods. One involves use of a
DRB. If this test method is desired, refer to the Pow-
ertrain Diagnostic Test Procedures for charging and
speed control system manual.The other test method uses a volt/ohm meter. The
volt/ohm meter method is described in the following
tests.
If any information is needed concerning wiring,
refer to Group 8W, Wiring Diagrams (Fig. 2).
CAUTION: When test probing for voltage or conti-
nuity at electrical connectors, care must be taken
not to damage connector, terminals, or seals. If
these components are damaged, intermittent or
complete system failure may occur.
When electrical connections are removed, corrosion
should be removed from electrical terminals and a
light coating of Mopar Multi-Purpose Grease, or
equivalent, applied. Inspect connectors for damage
terminals.
A poor connection can cause a complete or inter-
mittent malfunction and is also the only connection
in the circuit, that can not be tested. For this reason,
a loose connection may be misdiagnosed as a compo-
nent malfunction.
SPEED CONTROL DIAGNOSTIC TROUBLE CODES
Hex Code DRB Scan Tool Display Description of Diagnostic Trouble
Code
23 No Vehicle Speed Sensor Signal No vehicle distance (speed) sensor
signal detected during road load
conditions.
OF Speed Control Solenoid Circuits An open or shorted condition
detected in the Speed Control
vacuum or vent solenoid circuits.
56 MUX S/C Switch High Speed Control switch input above
the maximum acceptable voltage.
57 MUX S/C Switch Low Speed Control switch input below
the minimum acceptable voltage.
52 S/C Power Relay Or 12V Driver
CircuitMalfunction detected with power
feed to speed control servo solnoids.
Check Engine Lamp will illuminate during engine operation if this Diagnostic Trouble Code was recorded.
8H - 4 VEHICLE SPEED CONTROL SYSTEMNS
DIAGNOSIS AND TESTING (Continued)
VACUUM SUPPLY TEST
(1) Disconnect vacuum hose at the servo and
install a vacuum gauge in the hose (Fig. 7).
(2) Start engine and observe gauge at idle. Vac-
uum gauge should read at least ten inches of mer-
cury. Shut off engine, the vacuum should continue to
hold 10 inches of mercury.
(3) If vacuum does not meet this requirement,
check and correct the following vacuum leaks in the
vacuum lines, check valve, vacuum reservoir or poor
engine performance.
VEHICLE SPEED SENSOR
For diagnosis and testing of the Vehicle Speed Sen-
sor (VSS), refer to the appropriate Powertrain Diag-
nostic Procedures service manual. Also refer to the
DRB scan tool.
REMOVAL AND INSTALLATION
SPEED CONTROL SERVO
REMOVAL
(1) Release hood latch and open hood.
(2) On vehicles with 3.3/3.8 L engine, remove air
cleaner resonator. Refer to Group 14, Fuel System for
proper procedure.
(3) Disconnect the throttle and speed control cable
ends from throttle body (Fig. 8).
(4) Depress lock tabs holding speed control cable
casing to cable mount bracket (Fig. 9).(5) Disconnect vacuum line from nipple on air
intake plenum.
(6) Remove tie wrap holding vacuum line, throttle
cable, and speed control cable together.
(7) Remove bolt holding speed control servo to side
of battery tray/vacuum reservoir (Fig. 10).
(8) Remove speed control servo from battery tray.
(9) Disconnect wire connector from speed control
servo.
(10) Disconnect vacuum line from speed control
servo that leads to the battery tray/vacuum reservoir.
(11) Remove speed control servo.
Fig. 7 Vacuum Gauge Test
Fig. 8 Speed Control Cable End
Fig. 9 Speed Control Cable Case and Vacuum
LineÐTypical
8H - 8 VEHICLE SPEED CONTROL SYSTEMNS
DIAGNOSIS AND TESTING (Continued)
STEP IS NOT DONE A DIAGONSTIC TROUBLE
CODE (DTC) MAY BE SET.
VACUUM RESEROIR
REMOVAL
(1) Disconnect negative cable from battery.
(2) Remove battery, Refer to Group 8B, for Battery
Removal/Installation
(3) Remove battery tray.
(4) Disconnect vacuum hoses from vacuum reser-
voir
INSTALLATION
(1) Connect vacuum hoses to vacuum reservoir.
(2) Install battery tray
(3) Install battery, Refer to Group 8B, for Battery
Removal/Installation.
(4) Connect negative cable to battery.
VEHICLE SPEED SENSOR
For Removal/Installation, refer to Vehicle Speed
Sensor in Group 14, Fuel Injections.
Fig. 12 Speed Control Cable
8H - 10 VEHICLE SPEED CONTROL SYSTEMNS
REMOVAL AND INSTALLATION (Continued)