
multiple engine sensors have failed, repair ground between splice and
PCM.
12) Connect jumper wire between OPS connector terminals. If
oil pressure warning indicator illuminates, replace OPS. If oil
pressure warning indicator does not illuminate, go to next step.
13) Do not remove jumper wire. Disconnect PCM Black connector
C2. PCM is located in engine compartment on right inner fender. Using
an external ohmmeter, measure resistance between ground and PCM White
connector C2 terminal No. 23 (Gray/Orange wire). If resistance is less\
than 5 ohms, replace PCM. If resistance is 5 ohms or more, repair open
Gray/Orange wire.
14) Check cooling system operation. If cooling system is
operating properly, go to next step. If cooling system is not
operating properly, repair engine cooling problem.
15) Using scan tool, select PCM MONITOR under SYSTEM TESTS.
If scan tool displays PCM ACTIVE ON BUS, system is currently
functioning properly. If scan tool does not display PCM ACTIVE ON BUS,
go to appropriate VEHICLE COMMUNICATIONS article.
16) Using scan tool, select MODULE ENGINE CONTROLLER. Read
PCM DTCs. If scan tool displays any charging system related DTCs, go
to appropriate SELF-DIAGNOSTICS article in ENGINE PERFORMANCE section
and repair DTC as necessary. If scan tool does not display any
charging system related DTCs, go to next step.
17) Check charging system operation. If charging system is
operating properly, replace instrument cluster. If charging system is
not operating properly, repair engine charging problem.
18) Using scan tool, select BODY COMPUTER MONITORS. Read CCD
BUS ENGINE INFO. If scan tool displays engine RPM, replace instrument
cluster. If scan tool does not display engine RPM, replace PCM.
OVERHEAD CONSOLE CONCERNS
AVERAGE MPH/FUEL ECON INOPERATIVE OR WRONG (CMTC FAILS TO
RESPOND TO INSTRUMENT CLUSTER DIMMING, DISTANCE TO EMPTY
INOPERATIVE OR WRONG, ELAPSED TIME INOPERATIVE/WRONG, SWITCH
ON CMTC INOPERATIVE, TRIP ODOMETER INOPERATIVE/WRONG)
NOTE: If any listed symptoms exist, Compass Mini-Trip computer
(CMTC) is defective. Replace CMTC. Perform VERIFICATION TEST
VER- 1A after each repair.
CMTC SHOWS FAILED
NOTE: For connector terminal identification and wiring diagrams,
see BODY CONTROL COMPUTER - INTRODUCTION article. Perform
VERIFICATION TEST VER-1A after each repair.
Using scan tool, perform AUTO SELF TEST. If CMTC shows
failed, replace CMTC. If CMTC does not show failed, system is
currently functioning properly.
CMTC SEGMENTS FAIL TO LIGHT UP
NOTE: For connector terminal identification and wiring diagrams,
see BODY CONTROL COMPUTER - INTRODUCTION article. Perform
VERIFICATION TEST VER-1A after each repair.
Using scan tool, perform AUTO SELF TEST. If CMTC segments
fail to illuminate, replace CMTC. If CMTC segments all illuminate
properly, system is currently functioning properly.
INCORRECT READING BEYOND +/- 5

and make an informed decision about how to proceed.
BRAKES
SERVICE PROCEDURES REQUIRED & SUGGESTED FOR PROPER
VEHICLE OPERATION
Some states may have specifications that differ from OEM.
Check your local/state regulations. Where state or local laws are
stricter, they take precedence over these guidelines.
ACCELEROMETERS (G SENSOR OR LATERAL)
ACCELEROMETER INSPECTION \
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Condition Code Procedure
Broken .................. A ............ Require replacement.
Connector loose ......... A .. Require repair or replacement.
Loose ................... B .. Require repair or replacement.
Missing ................. C ............ Require replacement.
Out of position ......... B ....... Require re-positioning to
vehicle manufacturer's
specifications.
Output signal incorrect . B ............ Require replacement.
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ACCUMULATORS
ACCUMULATOR INSPECTION \
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Condition Code Procedure
Leaking ................. B ............ Require replacement.
Missing ................. C ............ Require replacement.
Pre-charge incorrect .... B ............ Require replacement.
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ANCHOR PINS
See BACKING PLATES .
ANTI-LOCK BRAKE SYSTEMS
NOTE: Anti-lock brakes are an integral part of the brake system. It
is essential that the anti-lock brakes function properly when
brake service is performed.
Anti-lock brake systems are commonly referred to as "ABS" and
will be referred to as "ABS" throughout these guidelines. Some ABS
components also function as part of a traction control system (TCS).
WARNING: When diagnosing and servicing high pressure components,
observe safety procedures and equipment requirements
established by the vehicle manufacturer to reduce the
possibility of serious personal injury.
NOTE: Intermittent electrical conditions are often caused by a loss
of ground, poor connection, or water intrusion into the
wiring harness.

1) Start engine, and check booster vacuum hose connections. A
hissing noise indicates a vacuum leak. Repair any vacuum leaks before
proceeding. Stop engine, and shift transmission into Neutral. Pump
brake pedal until all vacuum reserve in booster is depleted.
2) Hold brake pedal under light pressure. If pedal does not
hold firm and falls away, master cylinder may be faulty. Bleed system
using appropriate method, and repeat step 1). See BLEEDING PROCEDURES
under BLEEDING BRAKE SYSTEM.
3) If pedal still does not hold firm, master cylinder is
faulty. If pedal holds firm, start engine and observe pedal height. If
pedal height change is not apparent, power booster or vacuum check
valve is faulty. Install good check valve, and repeat steps 1) and 2).\
If pedal falls away slightly under light pressure and then holds firm,
go to next step .
4) Start engine. Release brake pedal. Increase engine speed
to 1500 RPM. Close throttle and immediately turn off ignition. Wait at
least 90 seconds, and try brake action again. Booster should provide 2
or more vacuum assisted pedal applications. If vacuum assist is not
provided, perform booster and check valve vacuum tests.
POWER BRAKE BOOSTER VACUUM TEST
Connect vacuum gauge to booster check valve using "T"
fitting. Start engine, and run at idle speed for one minute. Clamp
hose shut between vacuum source and check valve. Stop engine, and
observe vacuum gauge. If vacuum drops more than one in. Hg within 15
seconds, booster diaphragm or check valve is faulty.
POWER BRAKE BOOSTER CHECK VALVE TEST
Disconnect vacuum hose from check valve. Remove check valve
and valve seal from booster. Use a hand-operated vacuum pump for
testing. Apply 15-20 in. Hg at large end of check valve. Vacuum should
hold steady. If gauge on pump indicates vacuum loss, check valve is
faulty and should be replaced.
COMBINATION VALVE METERING VALVE TEST
Metering valve operation can be checked visually with aid of
an assistant. While an assistant applies and releases brake pedal,
observe metering valve stem. If valve is operating correctly, stem
will extend slightly when brakes are applied, and contract when brakes
are released. If valve is faulty, replace combination valve assembly.
COMBINATION VALVE PRESSURE DIFFERENTIAL SWITCH TEST
1) Using an assistant, apply brake pedal. Observe brake
warning light. Raise and support vehicle, and connect a bleed hose to
one rear wheel cylinder. Submerge other end of hose into container
partially filled with brake fluid. Have assistant press and hold brake
pedal down while observing brake warning light. Open bleeder screw. If
warning light glows, switch is operating properly.
2) If warning light fails to glow, check circuit fuse, bulb
and wiring. Repair as necessary. Repeat step 1). If warning light
fails to glow, check brakelight, parking brake switches and related
wiring. Repair as necessary. Repeat step 1). If warning light fails to
glow, pressure differential switch is faulty. Replace combination
valve assembly, and bleed brake system. Verify proper valve operation.
REMOVAL & INSTALLATION

pads at this time. On models with removable hub, install hub on rotor.
Install wheel and tire assembly. Tighten lug nuts so they are snug,
but DO NOT tighten to final torque specifications.
3) While rotating wheel, tighten adjuster nut sufficiently to
seat bearing. Loosen nut and retighten while still rotating wheel.
Back off adjuster nut to completely release bearing preload torque.
Ensure endplay of .001-.003" (.025-.076 mm). Install lock nut and NEW
cotter pin. If necessary, tighten lock nut slightly to align cotter
pin hole. Install grease cap. Tighten caliper bolts and lug nuts to
specification. See TORQUE SPECIFICATIONS table. To complete
installation, reverse remove procedure.
Removal (Ram Pickup With 8 Studs)
1) Raise and support vehicle. Remove wheel. Remove hub
extension, if equipped. Remove brake caliper. Support caliper aside.
2) On models with removable adapter hub, remove hub from
rotor. On models with one-piece hub and rotor assembly, remove cotter
pin from rotor hub nut. Remove nut. Disconnect ABS wheel speed sensor
wire (if equipped), and remove from frame and steering knuckle. Remove\
bolts securing hub to steering knuckle from inboard side of steering
knuckle. Remove rotor and hub assembly.
Installation
1) Apply anti-seize compound to drive shaft splines. Replace
grease seal in steering knuckle, if necessary. Insert 2 rearmost top
and bottom rotor hub bolts in steering knuckle so they extend through
back of knuckle. Install hub spacer, ensuring flat on space is
positioned to rear. Use chassis grease to hold spacer in position, if
necessary.
NOTE: If equipped with wheel speed sensor, brake shield must be
positioned on hub bearing, and sensor wire must be at top of
knuckle.
2) Align rotor hub with drive shaft and install hub assembly.
Align bolt holes in hub flange with bolts previously installed. Start
nuts on flange bolts sufficiently to hold assembly in place. Install
remaining bolts, and tighten all bolts to specification. See TORQUE
SPECIFICATIONS table.
3) Install washer and hub nut. Tighten nut securely. Install
NEW cotter pin. Install grease cap. Install caliper. Tighten caliper
bolts and lug nuts to specification. See TORQUE SPECIFICATIONS table.
To complete installation, reverse remove procedure.
REAR BRAKE SHOES
WARNING: Use water or brake cleaner to clean brake parts. DO NOT use
compressed air to remove dirt and dust.
Removal (Dakota & Ram Van)
1) Remove wheel and drum. Note how secondary spring overlaps
primary return spring. Using spring remover, remove brake shoe return
springs. Slide automatic adjuster cable off anchor. Disconnect cable
from adjusting lever.
2) Remove cable, cable guide and anchor plate. See Figs. 3,
4, and 5. Disconnect adjusting lever return spring from lever. Remove
lever and return spring from pivot pin. Remove shoe-to-shoe spring.
Spread shoes, and remove adjustment star wheel.
3) Remove shoe retainers, springs and pins. Remove parking
brake lever from secondary shoe. Remove shoes and parking brake strut
with spring.

being replaced, remove booster check valve and seal.
Installation
1) If new booster is being installed, install check valve and
seal. Position booster on dash, and install lock nuts on booster
mounting studs finger tight. Install booster push rod on brake pedal
pin, and secure rod with NEW retaining clip.
2) Tighten booster lock nuts to specification. Install master
cylinder on booster, and tighten mounting nuts to specification. See
TORQUE SPECIFICATIONS table. Connect vacuum hose to booster check
valve. Start vehicle and check booster operation.
COMBINATION VALVE
Removal & Installation
Raise and support vehicle. Mark brakelines for assembly
reference. Disconnect parking brake cable from clip on valve, if
necessary. Disconnect brake warning light connection at switch.
Disconnect all brake hydraulic lines at valve. Cap brakelines to
prevent dirt from entering system. Remove valve. To install, reverse
removal procedures. Bleed brake system. See BLEEDING PROCEDURES under
BLEEDING BRAKE SYSTEM.
AXLE BEARING & SEAL (FULL FLOATING AXLE)
Removal & Installation (Ram Pickup With 12" & 13" Drums)
1) Raise and support vehicle. Remove wheel. Remove axle shaft
nuts and washers. Strike center of axle flange to free cones. Remove
axle shaft and gasket.
2) Straighten and remove nut lock. Remove adjustment nut and
outer bearing. Remove drum assembly. Remove seal and inner bearing
from drum assembly.
3) Pack inner bearing, and install inner bearing and seal in
drum. Install drum assembly, outer bearing and adjustment nut. While
rotating drum, tighten adjustment nut to specification. See TORQUE
SPECIFICATIONS table.
4) Back off adjustment nut 1/8 turn to obtain .001-.010" (0.
025-0.254 mm) end play. Bend nut lock into spindle keyway. Install
gasket and axle shaft. Install wheel, and lower vehicle. See TORQUE
SPECIFICATIONS table.
OVERHAUL
NOTE: Use illustrations when overhauling components. See
Figs. 2-6.
DISC BRAKE SPECIFICATIONS
DISC BRAKE SPECIFICATIONS \
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Application In. (mm)\
Disc Diameter
Dakota ............................................... 11.30 (287)\
Ram Pickup
1/2 Ton ............................................. 11.57 (294)\
3/4 & 1 Ton ......................................... 12.50 (318)\
Ram Van
1/2 & 3/4 Ton ....................................... 11.75 (299)\
1 Ton ............................................... 12.82 (326)\
Lateral Runout

operator's foot off accelerator pedal, S/C compensates for excessive
S/C cable slack. If lift foot sets are continually used, speed control
overshoot/undershoot condition will develop.
To "unlearn" overshoot/undershoot condition, operator must
press and release set button while maintaining desired speed with
accelerator pedal, then turn S/C switch to OFF position after waiting
10 seconds. This procedure must be repeated 10-15 times to completely
unlearn overshoot/undershoot condition.
COMPONENT TESTS
WARNING: Vehicle is equipped with an air bag. Air bag must be
deactivated before servicing speed control components on or
around steering column. See appropriate AIR BAG RESTRAINT
SYSTEMS article.
NOTE: For component locations, See COMPONENT LOCATIONS. For
connector terminal identification, see CONNECTOR
IDENTIFICATION. For wiring diagram, see WIRING DIAGRAMS.
BRAKE SWITCH
Disconnect brake switch 6-pin connector. Using an ohmmeter,
check for continuity at brake switch. See Fig. 1. If continuity is not
as specified in BRAKE SWITCH CONTINUITY table, check brake switch
adjustment. See BRAKE SWITCH under REMOVAL & INSTALLATION. If brake
switch adjustment is okay, replace defective brake switch.
BRAKE SWITCH CONTINUITY
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Switch Plunger Check Between Continuity
Position Terminals
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Released 5 & 6 Yes
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\b \
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\b \
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Depressed 1 & 2 Yes
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3 & 4 Yes
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SPEED CONTROL SERVO
1) Start engine. Disconnect Speed Control (S/C) servo 4-pin
connector. Turn S/C on. Using a voltmeter, check voltage at S/C servo
connector terminal No. 3 (Dark Blue/Red wire). Battery voltage should
exist when brake pedal is not depressed. If battery voltage exists, go
to next step. If battery voltage does not exist, check circuit between
brake switch and S/C servo. See WIRING DIAGRAMS.
2) Connect a jumper wire between S/C servo pin No. 3 and S/C
servo connector terminal No. 3. Check voltage at S/C servo pins No. 1,
2 and 4. If battery voltage does not exist, replace S/C servo. If
battery voltage exists, go to next step.
3) Turn ignition off. Check for continuity between S/C servo
connector terminal No. 4 and ground. If continuity exists, test is
complete. If continuity does not exist, repair open ground circuit as
necessary.
VACUUM SUPPLY
Gasoline Engines
1) Disconnect vacuum hose at speed control servo. Install
vacuum gauge to disconnected vacuum hose. Start engine and observe

Fig. 4: Identifying Speed Control (S/C) Servo Connector Terminals
Courtesy of Chrysler Corp.
SELF-DIAGNOSTIC SYSTEM
WARNING: Vehicle is equipped with an air bag. Air bag must be
deactivated before servicing speed control components on or
around steering column. See AIR BAG RESTRAINT SYSTEMS -
TRUCKS article.
SERVICE PRECAUTIONS
Before proceeding with diagnosis, the following precautions
must be followed:
* When using Diagnostic Trouble Code (FTC) tests for diagnosis,
DO NOT skip any steps, or incorrect diagnosis may result.
Always perform indicated verification procedure after repairs are

10) Depress and release CANCEL switch. If S/C disengages, go
to next step. If S/C did not disengage, repair is not complete. Check
for related TSBs and return to TROUBLE SHOOTING, if necessary.
11) Ensure vehicle speed is greater than 35 MPH. Engage speed
control. Turn S/C on/off switch to OFF position. If speed control
disengages, system is operating correctly. Repair is complete. If
speed control does not disengage, repair is not complete. Check for
related TSBs and return to TROUBLE SHOOTING, if necessary.
TEST VER-5A
NOTE: If PCM has been replaced and correct VIN and mileage have not
been programmed, a FTC will be set in ABS and air bag
modules. If vehicle is equipped with a Sentry Key Immobilizer
Module (SKIM), sentry key data must be updated to enable
starting. See COMPUTER RELEARN PROCEDURES article in GENERAL
INFORMATION.
1) If vehicle is not equipped with a diesel engine, go to
next step. If vehicle is equipped with a diesel engine, and PCM has
been disconnected or replaced, battery has been disconnected, or
Accelerator Pedal Position Sensor (APPS) has been disconnected or
replaced, APPS calibration must be programmed into PCM (diesel only).
Turn ignition on. Slowly press accelerator pedal to floor and slowly
release. DO NOT attempt to adjust screws or disassemble APPS. Go to
next step.
2) On all engines, if vehicle is equipped with ABS or air
bag, enter correct VIN and mileage in PCM. Erase DTCs in ABS and air
bag modules. Inspect vehicle to ensure all engine and speed control
system components are connected.
3) If there are any DTCs that have not been repaired, go to
SELF-DIAGNOSTIC SYSTEM. After all DTCs have been repaired, run
appropriate monitor for previously repaired FTC.
4) Connect scan tool to DLC. Ensure fuel tank is at least 1/4
full. Turn off all accessories. Allow PCM to run appropriate monitor
and increment appropriate good trip. Enabling conditions must be met
before monitor will run.
5) Using scan tool, monitor pretest enabling conditions until
all conditions have been met. Once enabling conditions have been met,
monitor appropriate monitor.
6) If repaired FTC has reset or was seen in monitor while on
road test, repair is not complete. Check for TSBs or flash updates and
return to TROUBLE SHOOTING.
7) If appropriate monitor ran, good trip counter incremented
and no DTCs have been set, repair is complete.
REMOVAL & INSTALLATION
WARNING: Vehicle is equipped with an air bag. Air bag must be
deactivated before servicing speed control components on or
around steering column. See AIR BAG RESTRAINT SYSTEMS -
TRUCKS article.
CAUTION: When battery is disconnected, vehicle computer and memory
systems may lose memory data. Driveability problems may exist
until computer systems have completed a relearn cycle. See
COMPUTER RELEARN PROCEDURES article in GENERAL INFORMATION
before disconnecting battery.
BRAKE SWITCH
Removal