1998 DODGE RAM 1500 transmission

CABLE
DESCRIPTION
The speed control servo cable is connected between
the speed control vacuum servo diaphragm and the
throttle body control linkage. This cable is used with
3.7L/4.7L gas powered engines only. It is also used if
equipped with a 5.9L diesel engine equipped with an
automatic transmission.
A speed control servo cableis not usedif equipped
with either a 5.9L diesel engine equipped with a
manual transmission, or any 5.7L engine/transmis-
sion combinations.
OPERATION
This cable causes the throttle control linkage to
open or close the throttle valve in response to move-
ment of the vacuum servo diaphragm.
REMOVAL
3.7L / 4.7L GAS
(1) Disconnect negative battery cable at battery.
(2) Remove air intake tube at top of throttle body.
The accelerator cable must be partially removed to
gain access to speed control cable.
(3) Hold throttle in wide open position. While held
in this position, slide throttle cable pin (Fig. 1) from
throttle body bellcrank.
(4) Using a pick or small screwdriver, press release
tab (Fig. 2) to release plastic cable mount from
bracket.Press on tab only enough to release
cable from bracket. If tab is pressed too much,
it will be broken.Slide plastic mount (Fig. 2)
towards right side of vehicle to remove throttle cable
from throttle body bracket.
(5) Using finger pressure only, disconnect servo
cable connector (Fig. 3) at throttle body bellcrank pin
by pushing connector off bellcrank pin towards front
of vehicle.DO NOT try to pull connector off per-
pendicular to the bellcrank pin. Connector will
be broken.
(6) Slide speed control cable plastic mount towards
right of vehicle to remove cable from throttle body
bracket (Fig. 4).
(7) Remove servo cable from servo. Refer to Servo
Removal/Installation.
5.9L Diesel Ð Auto. Trans.
(1) Disconnect both negative battery cables at both
batteries.
(2) Remove cable/lever/linkage cover. Refer to
Speed Control Servo Removal/Installation.
(3) Remove (disconnect) servo cable from servo.
Refer to Speed Control Servo Removal/Installation.(4) Using finger pressure only, disconnect end of
servo cable from throttle lever pin by pulling forward
on connector while holding lever rearward (Fig. 5).
DO NOT try to pull connector off perpendicular
to lever pin. Connector will be broken.
(5) Squeeze 2 pinch tabs (Fig. 5) on sides of speed
control cable at mounting bracket and push cable
rearward out of bracket.
Fig. 1 THROTTLE CABLE PIN - 3.7L / 4.7L
1 - THROTTLE CABLE PIN
2 - THROTTLE BODY BELLCRANK
3 - PUSH UP HERE
Fig. 2 THROTTLE CABLE RELEASE TAB - 3.7L /
4.7L
1 - THROTTLE CABLE
2 - RELEASE TAB
3 - PICK OR SCREWDRIVER
4 - PLASTIC CABLE MOUNT
8P - 4 SPEED CONTROLDR

(5) Before starting engine, operate accelerator
pedal to check for any binding.
(6) Install cable/lever cover.
SERVO
DESCRIPTION
A speed control servo is not used with any
5.7L V-8 engine, or with the 5.9L diesel engine
when equipped with a manual transmission.
The speed control servo is attached to the bottom
of the battery tray.
The servo unit consists of a solenoid valve body,
and a vacuum chamber. The solenoid valve body con-
tains three solenoids:
²Vacuum
²Vent
²Dump
The vacuum chamber contains a diaphragm with a
cable attached to control the throttle linkage.
OPERATION
A speed control servo is not used with any
5.7L V-8 engine, or with the 5.9L diesel engine
when equipped with a manual transmission.
The following information applies only to
vehicles equipped with a mechanical servo.
When/if a servo is used on gasoline powered vehi-
cles, the Powertrain Control Module (PCM) controls
the solenoid valve body. When/if a servo is used on
certain diesel powered vehicles, the Engine Control
Module (ECM) controls the solenoid 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 ser-
viced only as a complete assembly.
Power is supplied to the servo's by the PCM/ECM
through the brake switch. The PCM/ECM controls
the ground path for the vacuum and vent solenoids.
The dump solenoid is energized anytime it receives
power. If power to the dump solenoid is interrupted,
the solenoid dumps vacuum in the servo. This pro-
vides a safety backup to the vent and vacuum sole-
noids.
The vacuum and vent solenoids must be grounded
at the PCM/ECM to operate. When the PCM/ECM
grounds the vacuum servo solenoid, the solenoid
allows vacuum to enter the servo and pull open the
throttle plate using the cable. When the PCM/ECM
breaks the ground, the solenoid closes and no more
vacuum is allowed to enter the servo. The PCM/ECM
also operates the vent solenoid via ground. The vent
solenoid opens and closes a passage to bleed or hold
vacuum in the servo as required.The PCM/ECM duty cycles the vacuum and vent
solenoids to maintain the set speed, or to accelerate
and decelerate the vehicle. To increase throttle open-
ing, the PCM/ECM grounds the vacuum and vent
solenoids. To decrease throttle opening, the PCM/
ECM removes the grounds from the vacuum and
vent solenoids. When the brake is released, if vehicle
speed exceeds 30 mph to resume, 35 mph to set, and
the RES/ACCEL switch has been depressed, ground
for the vent and vacuum circuits is restored.
REMOVAL
The speed control servo assembly is attached to the
bottom of the battery tray (Fig. 6).
(1) Disconnect negative battery cable at battery
(both cables at both batteries if diesel).
(2) To gain access to servo, remove plastic wheel-
house splash shield over left-front wheel.
(3) Disconnect vacuum line at servo (Fig. 6).
(4) Disconnect electrical connector at servo (Fig. 6).
(5) Remove 3 servo mounting screws (Fig. 6).
Depending on engine application, different sets of
mounting lugs (Fig. 6) are used to support servo to
battery tray. While removing, note proper lugs.
(6) Disconnect servo cable at throttle body. Refer to
Servo Cable Removal/Installation.
(7) Remove 2 mounting nuts holding servo cable
sleeve to bracket (Fig. 7).
(8) Pull speed control cable sleeve and servo away
from servo mounting bracket to expose cable retain-
ing clip (Fig. 7) and remove clip. Note: The servo
mounting bracket displayed in (Fig. 7) is a typical
bracket and may/may not be applicable to this model
vehicle.
(9) Remove servo from mounting bracket. While
removing, note orientation of servo to bracket.
INSTALLATION
(1) Position servo to mounting bracket (Fig. 7).
(2) Align hole in cable connector with hole in servo
pin. Install cable-to-servo retaining clip (Fig. 7).
(3) Insert servo mounting studs through holes in
servo mounting bracket.
(4) Install 2 servo-to-mounting bracket nuts and
tighten. Refer to torque specifications.
(5) Position servo assembly to correct mounting
lugs on battery tray (Fig. 6) and install 3 screws.
Tighten 3 screws. Refer to torque specifications.
(6) Connect vacuum line at servo.
(7) Connect electrical connector at servo.
(8) Connect servo cable to throttle body. Refer to
servo Cable Removal/Installation.
(9) Install left-front wheel-well liner.
(10) Connect negative battery cable to battery
(connect both cables if diesel).
8P - 6 SPEED CONTROLDR
CABLE (Continued)

(11) Before starting engine, operate accelerator
pedal to check for any binding.
SWITCH
DESCRIPTION
Two separate switch pods operate the speed control
system. The steering-wheel-mounted switches use
multiplexed circuits to provide inputs to the PCM (to
the ECM for diesel) 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.
The individual switches cannot be repaired. If one
switch fails, the entire switch module must be
replaced.
Depending on engine control computer (JTEC
having a 3± plug connector or NGC having a 4±
plug connector), 2 types of switches are used.
Both types of switches are internally and exter-
nally different. The switch used with the NGC
system has an attached pigtail lead. The switch
used with the JTEC system does not have an
attached pigtail lead.
OPERATION
When speed control is selected by depressing the
ON, OFF switch, the PCM(ECM for diesel)allows
a set speed to be stored in its RAM for speed control.
To store a set speed, depress the SET switch while
the vehicle is moving at a speed between approxi-
mately 35 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
²Depressing the OFF switch
²Depressing the CANCEL switch.
The speed control can be disengaged also by any of
the following conditions:
²An indication of Park or Neutral (auto. trans.)
²The VSS signal increases at a rate of 10 mph
per second (indicates that the co-efficient of friction
between the road surface and tires is extremely low)
²Depressing the clutch pedal (manual trans.).
²Excessive engine rpm (indicates that the trans-
mission may be in a low gear)
²The VSS signal decreases at a rate of 10 mph
per second (indicates that the vehicle may have
decelerated at an extremely high rate)
²If the actual speed is not within 20 mph of the
set speed
Fig. 6 SPEED CONTROL SERVO LOCATION
1 - BATTERY TRAY
2 - MOUNTING LUGS
3 - SERVO
4 - ELEC. CONNEC.
5 - MOUNTING SCREWS (3)
6 - MOUNTING BRACKET
7 - VACUUM LINE
Fig. 7 SERVO CABLE CLIP REMOVE/INSTALL Ð
TYPICAL
1 - SERVO MOUNTING NUTS (2)
2 - SERVO
3 - CABLE RETAINING CLIP
4 - SERVO CABLE AND SLEEVE
DRSPEED CONTROL 8P - 7
SERVO (Continued)

The wiper high/low relay can be diagnosed using
conventional diagnostic tools and methods. However,
conventional diagnostic methods may not prove con-
clusive in the diagnosis of the instrument cluster, the
Front Control Module (FCM), or the electronic mes-
sage inputs to or outputs from the instrument cluster
and the FCM that control the operation of the wiper
high/low relay. The most reliable, efficient, and accu-
rate means to diagnose the wiper high/low relay, the
instrument cluster, the FCM, or the electronic mes-
sage inputs and outputs related to the wiper high/low
relay operation requires the use of a DRBIIItscan
tool. Refer to the appropriate diagnostic information.
DIAGNOSIS AND TESTING - WIPER HIGH/LOW
RELAY
The wiper high/low relay (Fig. 23) is located in the
Integrated Power Module (IPM) in the engine com-
partment near the battery. Refer to the appropriate
wiring information. The wiring information includes
wiring diagrams, proper wire and connector repair
procedures, details of wire harness routing and
retention, connector pin-out information and location
views for the various wire harness connectors, splices
and grounds.
(1) Remove the wiper high/low relay from the IPM.
(Refer to 8 - ELECTRICAL/WIPERS/WASHERS/
WIPER HIGH/LOW RELAY - REMOVAL).
(2) A relay in the de-energized position should
have continuity between terminals 87A and 30, and
no continuity between terminals 87 and 30. If OK, go
to Step 3. If not OK, replace the faulty relay.
(3) Resistance between terminals 85 and 86 (elec-
tromagnet) should be 75   8 ohms. If OK, go to Step
4. If not OK, replace the faulty relay.(4) Connect a battery to terminals 85 and 86.
There should now be continuity between terminals
30 and 87, and no continuity between terminals 87A
and 30. If OK, reinstall the relay and use a DRBIIIt
scan tool to perform further testing. Refer to the
appropriate diagnostic information.
REMOVAL
(1) Disconnect and isolate the battery negative
cable.
(2) Remove the cover from the Integrated Power
Module (IPM) (Fig. 24).
(3) Remove the wiper high/low relay by grasping it
firmly and pulling it straight out from the receptacle
in the IPM.
Fig. 23 ISO Micro Relay
30 - COMMON FEED
85 - COIL GROUND
86 - COIL BATTERY
87 - NORMALLY OPEN
87A - NORMALLY CLOSED
Fig. 24 Integrated Power Module
1 - 15 - CARTRIDGE FUSE
16 - 53 - BLADE FUSE
54 - HEATED MIRROR RELAY
55 - WIPER ON/OFF RELAY
56 - A/C CONDENSER FAN RELAY
57 - ENGINE CONTROL RELAY
58 - FUEL PUMP RELAY
59 - TRANSMISSION RELAY
60 - WIPER HIGH/LOW RELAY
61 - SPARE
62 - FOG LAMP RELAY
63 - ADJUSTABLE PEDAL RELAY
64 - A/C CLUTCH RELAY
65 - SPARE
66 - O2 RELAY
67 - SPARE
68 - SPARE
69 - SPARE
70 - SPARE
71 - SPARE
72 - STARTER RELAY
73 - PARK LAMP RELAY
DRWIPERS/WASHERS 8R - 21
WIPER HIGH/LOW RELAY (Continued)

INSTALLATION
(1) Position the wiper high/low relay to the proper
receptacle in the Integrated Power Module (IPM)
(Fig. 24).
(2) Align the wiper high/low relay terminals with
the terminal cavities in the IPM receptacle.
(3) Push firmly and evenly on the top of the wiper
high/low relay until the terminals are fully seated in
the terminal cavities in the IPM receptacle.
(4) Reinstall the cover onto the IPM.
(5) Reconnect the battery negative cable.
WIPER MODULE
DESCRIPTION
The wiper motor bracket is secured with two
screws below the wiper motor through two rubber
insulators to the bottom of the cowl plenum panel
beneath the cowl plenum cover/grille panel (Fig. 25).
Two screws secure the top of the wiper module
bracket to the cowl plenum panel through rubber
insulators located on the outboard end of each pivot
bracket. The ends of the wiper pivot shafts that pro-
trude through dedicated openings in the cowl plenum
cover/grille panel to drive the wiper arms and bladesare the only visible components of the wiper module.
The wiper module consists of the following major
components:
²Bracket- The wiper module bracket consists of
a long tubular steel main member that has a die cast
pivot bracket formation near each end where the two
wiper pivots are secured. A stamped steel clamp
secures the center of the tubular member to the die
cast bracket integral to the wiper motor with two
screws.
²Crank Arm- The wiper motor crank arm is a
stamped steel unit with a slotted hole on the driven
end that is secured to the wiper motor output shaft
with a nut, and has a ball stud secured to the drive
end.
²Linkage- Two stamped steel drive links con-
nect the wiper motor crank arm to the wiper pivot
lever arms. The left side drive link has a plastic sock-
et-type bushing on each end. The right side drive
link has a plastic socket-type bushing on one end,
and a plastic sleeve-type bushing on the other end.
The socket-type bushing on one end of each drive
link is snap-fit over the ball stud on the lever arm of
its respective pivot. The right side drive link sleeve-
type bushing end is then fit over the motor crank
arm ball stud, and the other socket-type bushing of
the left side drive link is snap-fit over the exposed
end of the wiper motor crank arm ball stud.
²Motor- The wiper motor features an integral
die cast bracket to which the wiper module bracket is
secured with a stamped steel clamp and two screws
near the top and which has two rubber insulated
mounting ears at the bottom. This die casting also
serves as the wiper motor transmission housing from
which the wiper motor output shaft exits. A nut
secures the wiper motor crank arm to the motor out-
put shaft. The two-speed permanent magnet wiper
motor features an integral transmission, an internal
park switch, and an internal automatic resetting cir-
cuit breaker.
²Pivots- The two front wiper pivots are secured
within the die cast pivot brackets on the outboard
ends of the wiper module main member. The lever
arms that extend from the center of the pivot shafts
each have a ball stud on their end. The upper end of
each pivot shaft where the wiper arms will be fas-
tened each has a serrated driver with a keyway. The
lower ends of the pivot shafts are installed through
lubricated bushings in the pivot brackets and are
secured with snap rings.
The wiper module cannot be adjusted or repaired.
If any component of the module is faulty or damaged,
the entire wiper module unit must be replaced.
Fig. 25 Wiper Module
1 - PIVOT BRACKET (2)
2 - TUBE
3 - CLAMP
4 - PIVOT SHAFT (2)
5 - INSULATOR (4)
6 - LINKAGE BUSHING (4)
7 - DRIVE LINK (2)
8 - PIVOT CRANK ARM (2)
9 - PIGTAIL WIRE CONNECTOR
10 - MOTOR CRANK ARM
11 - WIPER MOTOR
8R - 22 WIPERS/WASHERSDR
WIPER HIGH/LOW RELAY (Continued)

OPERATION
The wiper module operation is controlled by the
battery current inputs received by the wiper motor
through the wiper on/off and wiper high/low relays.
The wiper motor speed is controlled by current flow
to either the low speed or the high speed set of
brushes. The park switch is a single pole, single
throw, momentary switch within the wiper motor
that is mechanically actuated by the wiper motor
transmission components. The park switch alter-
nately opens and closes the wiper park switch sense
circuit to ground, depending upon the position of the
wipers on the glass. This feature allows the motor to
complete its current wipe cycle after the wiper sys-
tem has been turned Off, and to park the wiper
blades in the lowest portion of the wipe pattern. The
automatic resetting circuit breaker protects the
motor from overloads. The wiper motor crank arm,
the two wiper linkage members, and the two wiper
pivots mechanically convert the rotary output of the
wiper motor to the back and forth wiping motion of
the wiper arms and blades on the glass.
REMOVAL
(1) Remove both wiper arms from the wiper pivots.
(Refer to 8 - ELECTRICAL/WIPERS/WASHERS/
WIPER ARM - REMOVAL).
(2) Unlatch and open the hood.
(3) Disconnect and isolate the battery negative
cable.
(4) Remove the cowl plenum cover/grille panel
from over the cowl plenum. (Refer to 23 - BODY/EX-
TERIOR/COWL GRILLE - REMOVAL).
(5) Disconnect the left headlamp and dash wire
harness connector for the wiper motor from the
motor pigtail wire connector (Fig. 26).(6) Remove the two screws that secure the wiper
module to the top of the cowl plenum panel at the
pivot brackets.
(7) Remove the two screws that secure the wiper
module to the bottom of the cowl plenum panel.
(8) Remove the wiper module from the cowl ple-
num panel as a unit.
INSTALLATION
(1) Position the wiper module into the cowl ple-
num as a unit (Fig. 26).
(2) Install the two screws that secure the wiper
module to the top of the cowl plenum panel at the
pivot brackets. Tighten the screw on the driver side,
followed by the screw on the passenger side. Tighten
the screws to 7 N´m (60 in. lbs.).
(3) Install and tighten the screws that secure the
wiper module to the bottom of the cowl plenum
panel. Tighten the screw on the passenger side, fol-
lowed by the screw on the driver side. Tighten the
screws to 7 N´m (60 in. lbs.).
(4) Reconnect the left headlamp and dash wire
harness connector for the wiper motor to the motor
pigtail wire connector.
(5) Reinstall the cowl plenum cover/grille panel
over the cowl plenum. (Refer to 23 - BODY/EXTERI-
OR/COWL GRILLE - INSTALLATION).
(6) Reconnect the battery negative cable.
(7) Close and latch the hood.
(8) Reinstall both wiper arms onto the wiper piv-
ots. (Refer to 8 - ELECTRICAL/WIPERS/WASHERS/
WIPER ARMS - INSTALLATION).
DRWIPERS/WASHERS 8R - 23
WIPER MODULE (Continued)

(1) Remove the wiper on/off relay from the IPM.
(Refer to 8 - ELECTRICAL/WIPERS/WASHERS/
WIPER ON/OFF RELAY - REMOVAL).
(2) A relay in the de-energized position should
have continuity between terminals 87A and 30, and
no continuity between terminals 87 and 30. If OK, go
to Step 3. If not OK, replace the faulty relay.
(3) Resistance between terminals 85 and 86 (elec-
tromagnet) should be 75   8 ohms. If OK, go to Step
4. If not OK, replace the faulty relay.
(4) Connect a battery to terminals 85 and 86.
There should now be continuity between terminals
30 and 87, and no continuity between terminals 87A
and 30. If OK, reinstall the relay and use a DRBIIIt
scan tool to perform further testing. Refer to the
appropriate diagnostic information.
REMOVAL
(1) Disconnect and isolate the battery negative
cable.
(2) Remove the cover from the Integrated Power
Module (IPM) (Fig. 29).
(3) Remove the wiper on/off relay by grasping it
firmly and pulling it straight out from the receptacle
in the IPM.
INSTALLATION
(1) Position the wiper on/off relay to the proper
receptacle in the Integrated Power Module (IPM)
(Fig. 29).
(2) Align the wiper on/off relay terminals with the
terminal cavities in the IPM receptacle.
(3) Push firmly and evenly on the top of the wiper
on/off relay until the terminals are fully seated in the
terminal cavities in the IPM receptacle.
(4) Reinstall the cover onto the IPM.
(5) Reconnect the battery negative cable.
Fig. 29 Integrated Power Module
1 - 15 - CARTRIDGE FUSE
16 - 53 - BLADE FUSE
54 - HEATED MIRROR RELAY
55 - WIPER ON/OFF RELAY
56 - A/C CONDENSER FAN RELAY
57 - ENGINE CONTROL RELAY
58 - FUEL PUMP RELAY
59 - TRANSMISSION RELAY
60 - WIPER HIGH/LOW RELAY
61 - SPARE
62 - FOG LAMP RELAY
63 - ADJUSTABLE PEDAL RELAY
64 - A/C CLUTCH RELAY
65 - SPARE
66 - O2 RELAY
67 - SPARE
68 - SPARE
69 - SPARE
70 - SPARE
71 - SPARE
72 - STARTER RELAY
73 - PARK LAMP RELAY
8R - 26 WIPERS/WASHERSDR
WIPER ON/OFF RELAY (Continued)

WIRING
TABLE OF CONTENTS
page page
WIRING DIAGRAM INFORMATION....... 8W-01-1
COMPONENT INDEX.................. 8W-02-1
POWER DISTRIBUTION............... 8W-10-1
GROUND DISTRIBUTION.............. 8W-15-1
BUS COMMUNICATIONS.............. 8W-18-1
CHARGING SYSTEM.................. 8W-20-1
STARTING SYSTEM.................. 8W-21-1
FUEL/IGNITION SYSTEM.............. 8W-30-1
TRANSMISSION CONTROL SYSTEM..... 8W-31-1
VEHICLE SPEED CONTROL............ 8W-33-1
REAR WHEEL ANTILOCK BRAKES....... 8W-34-1
ALL WHEEL ANTILOCK BRAKES........ 8W-35-1
VEHICLE THEFT SECURITY SYSTEM..... 8W-39-1
INSTRUMENT CLUSTER............... 8W-40-1
HORN/CIGAR LIGHTER/POWER OUTLET . . 8W-41-1
AIR CONDITIONING.................. 8W-42-1
AIRBAG SYSTEM.................... 8W-43-1
INTERIOR LIGHTING.................. 8W-44-1AUDIO SYSTEM..................... 8W-47-1
REAR WINDOW DEFOGGER............ 8W-48-1
OVERHEAD CONSOLE................. 8W-49-1
FRONT LIGHTING.................... 8W-50-1
REAR LIGHTING..................... 8W-51-1
TURN SIGNALS...................... 8W-52-1
WIPERS............................ 8W-53-1
TRAILER TOW....................... 8W-54-1
NAVIGATION/TELECOMMUNICATION..... 8W-55-1
POWER WINDOWS................... 8W-60-1
POWER DOOR LOCKS................ 8W-61-1
POWER MIRRORS................... 8W-62-1
POWER SEATS...................... 8W-63-1
SPLICE INFORMATION................ 8W-70-1
CONNECTOR PIN-OUTS............... 8W-80-1
CONNECTOR/GROUND/SPLICE
LOCATION........................ 8W-91-1
POWER DISTRIBUTION............... 8W-97-1 DRWIRING 8W - 1