Control vacuum DODGE RAM 2001 Service Owner's Guide

to enter the servo and pull open the throttle plate
using the cable. When the PCM breaks the ground,
the solenoid closes and no more vacuum is allowed to
enter the servo. The PCM also operates the vent sole-
noid via ground. The vent solenoid opens and closes a
passage to bleed or hold vacuum in the servo as
required.
The PCM duty cycles the vacuum and vent sole-
noids to maintain the set speed, or to accelerate and
decelerate the vehicle. To increase throttle opening,
the PCM grounds the vacuum and vent solenoids. To
decrease throttle opening, the PCM 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
V-6/V-8 ENGINES
(1) Disconnect negative battery cable at battery.
(2) Disconnect electrical connector at servo (Fig. 4).
(3) Disconnect vacuum hose at servo.
(4) Disconnect servo cable at throttle body. Refer to
Servo Cable Removal/Installation in this group.(5) Remove three bolts retaining servo/servo
mounting bracket to side of battery tray (Fig. 5).
(6) Position servo assembly to gain access to 2
servo mounting nuts (Fig. 5) or (Fig. 6).
(7) Remove 2 mounting nuts holding servo cable
sleeve to bracket (Fig. 6).
(8) Pull speed control cable sleeve and servo away
from servo mounting bracket to expose cable retain-
ing clip (Fig. 6) and remove clip. Note: The servo
mounting bracket displayed in (Fig. 6) 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.
8.0L V-10 ENGINE
(1) Disconnect negative battery cable at battery.
(2) Disconnect positive battery cable at battery.
(3) Remove 2 bolts and battery holddown (Fig. 7).
(4) If equipped, pull up on battery heat shield to
remove it (Fig. 8).
(5) Remove battery from vehicle.
Fig. 3 Servo Cable at Throttle Lever
1 - PINCH (2) TABS
2 - CABLE MOUNTING BRACKET
3 - PINCH TABS (2)
4 - OFF
5 - THROTTLE CABLE
6 - THROTTLE LEVER
7 - THROTTLE LEVER PIN
8 - OFF
9 - CONNECTOR
10 - SPEED CONTROL CABLE
Fig. 4 Servo LocationÐRemoval/Installation
1 - BATTERY TRAY
2 - SERVO ELECTRICAL CONNECTOR
3 - SERVO BRACKET SCREWS (3)
8P - 6 SPEED CONTROLBR/BE
SPEED CONTROL SERVO (Continued)

(6) From under left front wheel opening, remove 2
forward battery tray nuts (Fig. 9).
(7) Remove 2 nuts and 2 bolts holding battery tray
to vehicle (Fig. 10).
(8) Disconnect servo cable at throttle body. Refer to
Servo Cable Removal/Installation in this group.(9) Position battery tray up far enough for access
to speed control servo electrical connector and vac-
uum line.
(10) Disconnect electrical connector and vacuum
line at servo.
(11) Position battery tray with attached servo
assembly to gain access to 2 servo mounting nuts
(Fig. 5) or (Fig. 6).
(12) Remove 2 mounting nuts holding servo cable
sleeve to bracket (Fig. 6).
Fig. 5 Servo Mounting at Battery Tray
1 - BATTERY TRAY
2 - SPEED CONTROL SERVO
3 - SERVO MOUNTING NUTS (2)
Fig. 6 Servo Cable Clip Remove/InstallÐTypical
1 - SERVO MOUNTING NUTS (2)
2 - SERVO
3 - CABLE RETAINING CLIP
4 - SERVO CABLE AND SLEEVE
Fig. 7 Battery Holddown
1 - REMOVE 2 BOLTS
2 - BATTERY HOLDDOWN STRAP
Fig. 8 Battery Heat Shield
1 - BATTERY HEAT SHIELD
BR/BESPEED CONTROL 8P - 7
SPEED CONTROL SERVO (Continued)

(9) Using finger pressure only, disconnect end of
servo cable from throttle lever pin by pulling forward
on connector while holding lever rearward (Fig. 16).
DO NOT try to pull connector off perpendicular
to lever pin. Connector will be broken.
(10) Position battery tray up far enough for access
to speed control servo electrical connector and vac-
uum line.
(11) Disconnect electrical connector and vacuum
line at servo.
(12) Position battery tray with attached servo
assembly to gain access to 2 servo mounting nuts
(Fig. 18) or (Fig. 19).
(13) Remove 2 mounting nuts holding servo cable
sleeve to bracket (Fig. 19).
(14) Pull speed control cable sleeve and servo away
from servo mounting bracket to expose cable retain-
ing clip (Fig. 19) and remove clip. Note: The servo
mounting bracket displayed in (Fig. 19) is a typical
bracket and may/may not be applicable to this model
vehicle.
(15) Remove servo from mounting bracket. While
removing, note orientation of servo to bracket.
INSTALLATION
V-6/V-8 ENGINES
(1) Position servo to mounting bracket.
(2) Align hole in cable connector with hole in servo
pin. Install cable-to-servo retaining clip.
(3) Insert servo studs through holes in servo
mounting bracket.
(4) Insert servo studs through holes in servo cable
sleeve.
(5) Install servo mounting nuts and tighten to 8.5
N´m (75 in. lbs.) torque.
(6) Connect vacuum line to servo.
(7) Connect electrical connector to servo terminals.
(8) Install three bolts retaining servo/servo mount-
ing bracket to battery tray.
(9) Connect servo cable to throttle body. Refer to
Servo Cable Removal/Installation in this group.
(10) Connect negative battery cable to battery.
(11) Before starting engine, operate accelerator
pedal to check for any binding.
Fig. 16 Servo Cable at Throttle Lever
1 - PINCH (2) TABS
2 - CABLE MOUNTING BRACKET
3 - PINCH TABS (2)
4 - OFF
5 - THROTTLE CABLE
6 - THROTTLE LEVER
7 - THROTTLE LEVER PIN
8 - OFF
9 - CONNECTOR
10 - SPEED CONTROL CABLE
Fig. 17 Servo LocationÐRemoval/Installation
1 - BATTERY TRAY
2 - SERVO ELECTRICAL CONNECTOR
3 - SERVO BRACKET SCREWS (3)
8P - 10 SPEED CONTROLBR/BE
SPEED CONTROL SERVO (Continued)

8.0L V-10 ENGINE
(1) Position servo to mounting bracket.
(2) Align hole in cable connector with hole in servo
pin. Install cable-to-servo retaining clip.
(3) Insert servo studs through holes in servo
mounting bracket.
(4) Insert servo studs through holes in servo cable
sleeve.
(5) Install servo mounting nuts and tighten to 8.5
N´m (75 in. lbs.) torque.
(6) Connect vacuum line to servo.
(7) Connect electrical connector to servo terminals.
(8) Connect servo cable to throttle body. Refer to
Servo Cable Removal/Installation in this group.
(9) Install battery tray. Tighten all battery tray
mounting hardware to 16 N´m (140 in. lbs.) torque.
(10) Position battery into battery tray.
(11) If equipped, install battery heat shield.
(12) Install battery holddown clamp. Tighten bolt
to 4 N´m (35 in. lbs.) torque.
(13) Connect positive battery cable to battery.
(14) Connect negative battery cable to battery.
(15) Before starting engine, operate accelerator
pedal to check for any binding.
INSTALLATION - DIESEL WITH AUTO. TRANS.
(1) Position servo to mounting bracket.
(2) Align hole in cable connector with hole in servo
pin. Install cable-to-servo retaining clip.
(3) Insert servo studs through holes in servo
mounting bracket.
(4) Insert servo studs through holes in servo cable
sleeve.
(5) Install servo mounting nuts and tighten to 8.5
N´m (75 in. lbs.) torque.
(6) Connect vacuum line to servo.
(7) Connect electrical connector to servo terminals.
(8) Connect servo cable to throttle lever by push-
ing cable connector rearward onto lever pin while
holding lever forward.
(9) Install battery tray. Tighten all battery tray
mounting hardware to 16 N´m (140 in. lbs.) torque.
(10) Position battery into battery tray.
(11) If equipped, install battery heat shield.
(12) Install battery holddown clamp. Tighten bolt
to 4 N´m (35 in. lbs.) torque.
(13) Connect positive battery cable to battery.
(14) Connect negative battery cables to both bat-
teries.
(15) Before starting engine, operate accelerator
pedal to check for any binding.
(16) Install cable/lever cover.
Fig. 18 Servo Mounting at Battery Tray
1 - BATTERY TRAY
2 - SPEED CONTROL SERVO
3 - SERVO MOUNTING NUTS (2)
Fig. 19 Servo Cable Clip Remove/InstallÐTypical
1 - SERVO MOUNTING NUTS (2)
2 - SERVO
3 - CABLE RETAINING CLIP
4 - SERVO CABLE AND SLEEVE
BR/BESPEED CONTROL 8P - 11
SPEED CONTROL SERVO (Continued)

²If the actual speed is not within 20 mph of the
set speedThe previous disengagement conditions are
programmed for added safety.
Once the speed control has been disengaged,
depressing the ACCEL switch restores the vehicle to
the target speed that was stored in the ECM's RAM.
NOTE: Depressing the OFF switch will erase the set
speed stored in the ECM's RAM.
If, while the speed control is engaged, the driver
wishes to increase vehicle speed, the ECM is pro-
grammed for an acceleration feature. With the
ACCEL switch held closed, the vehicle accelerates
slowly to the desired speed. The new target speed is
stored in the ECM's RAM when the ACCEL switch is
released. The ECM also has a9tap-up9feature in
which vehicle speed increases at a rate of approxi-
mately 2 mph for each momentary switch activation
of the ACCEL switch.
The ECM also provides a means to decelerate with-
out disengaging speed control. To decelerate from an
existing recorded target speed, depress and hold the
COAST switch until the desired speed is reached.
Then release the switch. The ON, OFF switch oper-
ates two components: the ECM's ON, OFF input, and
the battery voltage to the brake switch, which powers
the speed control servo.
REMOVAL
WARNING: BEFORE BEGINNING ANY AIRBAG SYS-
TEM COMPONENT REMOVAL OR INSTALLATION,
REMOVE AND ISOLATE THE NEGATIVE (-)
CABLE(S) FROM THE BATTERY. THIS IS THE ONLY
SURE WAY TO DISABLE THE AIRBAG SYSTEM.
THEN WAIT TWO MINUTES FOR SYSTEM CAPACI-
TOR TO DISCHARGE BEFORE FURTHER SYSTEM
SERVICE. FAILURE TO DO THIS COULD RESULT IN
ACCIDENTAL AIRBAG DEPLOYMENT AND POSSI-
BLE INJURY.
(1) Disconnect and isolate negative battery
cable(s).
(2) Remove airbag module. Refer to 8, Restraint
Systems for procedures.
(3) Remove switch-to-steering wheel mounting
screws (Fig. 20).
(4) Remove switch.
(5) Remove electrical connector at switch.
INSTALLATION
(1) Install electrical connector to switch.
(2) Install switch and mounting screws.
(3) Tighten screws to 3 N´m (26 in. lbs. +/± 2 in.
lbs.) torque.(4) Install airbag module. Refer to 8, Restraint
Systems for procedures.
(5) Connect negative battery cable(s).
VACUUM RESERVOIR
DESCRIPTION
Gasoline Powered Engines :A vacuum reservoir
is used to supply the vacuum needed to maintain
proper speed control operation when engine vacuum
drops, such as in climbing a grade while driving. A
one-way check valve is used in the vacuum line
between the reservoir and the vacuum source. This
check valve is used to trap engine vacuum in the res-
ervoir. On certain vehicle applications, this reservoir
is shared with the heating/air-conditioning system.
The vacuum reservoir cannot be repaired and must
be replaced if faulty.
Diesel Powered Engines With Auto. Trans. :A
vacuum reservoir is not used if equipped with a die-
sel powered engine. Instead, an engine driven pump
(vacuum pump) is used to supply vacuum for speed
control operation. This vacuum pump is used with
the diesel engine only if it is equipped with an auto-
matic transmission. Refer to Vacuum Pump in 9,
Engines for information.
REMOVAL
The vacuum reservoir is located under the plastic
cowel plenum cover at lower base of windshield. The
vacuum reservoir is not used if equipped with a die-
sel engine.
Fig. 20 Speed Control Switches
1 - MOUNTING SCREWS (2)
2 - SPEED CONTROL SWITCHES (2)
BR/BESPEED CONTROL 8P - 13
SWITCH (Continued)

(1) Disconnect and isolate battery negative cable.
(2) Remove both windshield wiper arm/blade
assemblies. Refer to 8, Wiper and Washer Systems.
(3) Remove rubber weather-strip at front edge of
cowel grill (Fig. 21).
(4) Release cowel grill plastic anchor screws (Fig.
22).
(5) Lift cowel plenum cover/grille panel from vehi-
cle far enough to access vacuum reservoir.
(6) Disconnect vacuum supply line from vacuum
reservoir (Fig. 23).
(7) Remove 2 vacuum reservoir mounting screws.
(8) Remove vacuum reservoir from vehicle.
INSTALLATION
The vacuum reservoir is located under the plastic
cowel plenum cover at lower base of windshield. The
vacuum reservoir is not used if equipped with a die-
sel engine.
(1) Install vacuum reservoir and two mounting
screws. Tighten screws to 2.2 N´m (20 in. lbs.) torque.
(2) Connect vacuum supply hose to vacuum reser-
voir.
(3) Position cowel plenum cover/grille panel to
vehicle.
(4) Install and tighten cowel cover fasteners to
vehicle body.
(5) Install rubber weather-strip at front edge of
cowel grill.
(6) Install windshield wiper arms. Refer to 8,
Wiper and Washer Systems.
(7) Connect negative battery to cable.
Fig. 21 Cowel Grille Panel Weather-strip
1 - COWL GRILLE
2 - WEATHERSTRIP
Fig. 22 Plastic Anchor Screws Remove/Install
1 - PLASTIC SCREW ANCHOR
2 - COWL GRILLE
Fig. 23 Vacuum Reservoir Remove/Install
1 - COWL PLENUM
2 - VACUUM RESERVOIR
8P - 14 SPEED CONTROLBR/BE
VACUUM RESERVOIR (Continued)

POWERTRAIN CONTROL MODULE C2 (GAS) - BLACK 32 WAY
CAV CIRCUIT FUNCTION
25 T13 18DB/BK (A/T) OUTPUT SPEED SENSOR GROUND
26 - -
27 G7 18WT/OR (A/T) VEHICLE SPEED SENSOR SIGNAL
28 T14 18LG/BK (A/T) OUTPUT SPEED SENSOR SIGNAL
29 T25 18LG/WT (A/T) GOVERNOR PRESSURE SENSOR SIGNAL
30 K30 18PK (A/T) TRANSMISSION CONTROL RELAY CONTROL
31 K7 18OR (A/T) 5V SUPPLY
32 - -
POWERTRAIN CONTROL MODULE C3 (DIESEL) - BLACK 32 WAY
CAV CIRCUIT FUNCTION
1 C13 18DB/OR A/C COMPRESSOR CLUTCH RELAY CONTROL
2- -
3 K51 18DB/YL AUTOMATIC SHUT DOWN RELAY CONTROL
4 V36 18TN/RD SPEED CONTROL VACUUM SOLENOID CONTROL
5 V35 18LG/RD SPEED CONTROL VENT SOLENOID CONTROL
6- -
7- -
8- -
9- -
10 - -
11 V32 18YL/RD SPEED CONTROL SUPPLY
12 A142 14DG/OR AUTOMATIC SHUT DOWN RELAY OUTPUT
13 T6 18OR/WT (A/T) OVERDRIVE OFF SWITCH SENSE
14 - -
15 K118 18PK/YL BATTERY TEMPERATURE SENSOR SIGNAL
16 - -
17 - -
18 - -
19 - -
20 - -
21 - -
22 C20 18BR A/C SWITCH SENSE
23 C90 18LG/WT A/C SELECT INPUT
24 V40 18WT/PK BRAKE SWITCH SENSE
25 T125 18DB GENERATOR SOURCE
26 K226 18DB/WT FUEL LEVEL SENSOR SIGNAL
27 D21 18PK/DB SCI TRANSMIT
28 D2 18WT/BK CCD BUS(-)
29 D220 18WT/VT SCI RECEIVE
30 D1 18VT/BR CCD BUS(+)
31 - -
32 V37 18RD/LG SPEED CONTROL SWITCH SIGNAL
BR/BE8W-80 CONNECTOR PIN-OUTS 8W - 80 - 69

POWERTRAIN CONTROL MODULE C3 (GAS) - BLACK 32 WAY
CAV CIRCUIT FUNCTION
1 C13 18DB/OR A/C COMPRESSOR CLUTCH RELAY CONTROL
2- -
3 K51 18DB/YL AUTOMATIC SHUT DOWN RELAY CONTROL
4 V36 18TN/RD SPEED CONTROL VACUUM SOLENOID CONTROL
5 V35 18LG/RD SPEED CONTROL VENT SOLENOID CONTROL
6- -
7- -
8 K199 18BR/VT (CALIFORNIA) OXYGEN SENSOR 1/1 HEATER CONTROL
9 K145 20DG/PK (CALIFORNIA) OXYGEN SENSOR DOWNSTREAM RELAY CONTROL
10 K106 18WT/DG LEAK DETECTION PUMP SOLENOID CONTROL
11 V32 18YL/RD SPEED CONTROL SUPPLY
12 A142 14DG/OR AUTOMATIC SHUT DOWN RELAY OUTPUT
13 T6 18OR/WT (A/T) OVERDRIVE OFF SWITCH SENSE
14 K107 18OR LEAK DETECTION PUMP SWITCH SENSE
15 K118 18PK/YL BATTERY TEMPERATURE SENSOR SIGNAL
16 K299 18BR.WT OXYGEN SENSOR 2/1 HEATER CONTROL
17 - -
18 - -
19 K31 18BR/WT FUEL PUMP RELAY CONTROL
20 K52 18PK/WT EVAPORATIVE EMISSION SOLENOID CONTROL
21 - -
22 C20 18BR A/C SWITCH SENSE
23 C90 18LG/WT A/C SELECT INPUT
24 V40 18WT/PK BRAKE SWITCH SENSE
25 T125 18DB GENERATOR SOURCE
26 K226 18DB/WT FUEL LEVEL SENSOR SIGNAL
27 D21 18PK/DB SCI TRANSMIT
28 D2 18WT/BK CCD BUS (-)
29 D20 18DG SCI RECEIVE
30 D1 18VT/BR CCD BUS (+)
31 - -
32 V37 18RD/LG SPEED CONTROL SWITCH SIGNAL
RADIO C1 - GRAY 7 WAY
CAV CIRCUIT FUNCTION
1- -
2 X55 18BR/RD LEFT FRONT DOOR SPEAKER (-)
3 X56 18DB/RD RIGHT FRONT DOOR SPEAKER (-)
4 E17 18YL/BK DAY BRIGHTNESS SENSE
5 E2 22OR PANEL LAMPS FEED
6 X12 16RD/WT FUSED IGNITION SWITCH OUTPUT (RUN-ACC)
7 M1 22PK FUSED B(+)
8W - 80 - 70 8W-80 CONNECTOR PIN-OUTSBR/BE

SEAT BELT SWITCH (STANDARD CAB) - BLACK 2 WAY
CAV CIRCUIT FUNCTION
1 G10 20LG/RD SEAT BELT SWITCH SENSE
2 Z2 20BK/LG GROUND
SEAT HEAT INTERFACE MODULE - 14 WAY
CAV CIRCUIT FUNCTION
1 P7 20LB/BK DRIVER HEATED SEAT SWITCH
2 P144 20BK/WT SEAT TEMPERATURE 5V SUPPLY
3 P130 16TN RIGHT SEAT HEATER B(+) DRIVER
4 F235 16RD B(+) TO HEATED SEAT MODULE
5 P131 16RD/DG LEFT SEAT HEATER B(+) DRIVER
6 F235 16RD B(+) TO HEATED SEAT MODULE
7 P142 22DB RIGHT SEAT TEMPERATURE SENSOR INPUT
8 P141 20TN/LB LEFT SEAT TEMPERATURE SENSOR INPUT
9 P8 20LB/WT PASSENGER HEATED SEAT SWITCH
10 P138 20VT/LG RIGHT SEAT LOW HEAT LED DRIVER
11 P140 20VT/BK RIGHT SEAT HIGH HEAT LED DRIVER
12 P137 20DG LEFT SEAT LOW HEAT LED DRIVER
13 Z2 18BK/LG GROUND
14 P139 20WT LEFT SEAT HIGH HEAT LED DRIVER
SPEED CONTROL SERVO - BLACK 4 WAY
CAV CIRCUIT FUNCTION
1 V36 20TN/RD SPEED CONTROL VACUUM SOLENOID CONTROL
2 V35 20LG/RD SPEED CONTROL VENT SOLENOID CONTROL
3 V30 20DB/RD SPEED CONTROL BRAKE SWITCH OUTPUT
4 Z1 20BK GROUND
TAILGATE LAMP (DUAL REAR WHEELS) - BLACK 2 WAY
CAV CIRCUIT FUNCTION
1 Z13 18BK GROUND
2 L7 18BK/YL HEADLAMP SWITCH OUTPUT
THROTTLE POSITION SENSOR (GAS)-3WAY
CAV CIRCUIT FUNCTION
1 K6 20VT/WT 5V OUTPUT
2 K22 18OR/DB THROTTLE POSITION SENSOR SIGNAL
3 K4 20BK/LB SENSOR GROUND
8W - 80 - 76 8W-80 CONNECTOR PIN-OUTSBR/BE

CONDITION POSSIBLE CAUSES CORRECTION
11. Faulty ignition cables 11. Replace any cracked or shorted
cables
12. Faulty ignition coil 12. Test and replace, as necessary (Refer
to 8 - ELECTRICAL/IGNITION
CONTROL/IGNITION COIL - REMOVAL).
ENGINE STALLS OR
ROUGH IDLE1. Carbon build-up on throttle plate 1. Remove throttle body and de-carbon.
(Refer to 14 - FUEL SYSTEM/FUEL
INJECTION/THROTTLE BODY -
REMOVAL).
2. Engine idle speed too low 2. Check Idle Air Control circuit. (Refer to
14 - FUEL SYSTEM/FUEL INJECTION/
IDLE AIR CONTROL MOTOR -
DESCRIPTION)
3. Worn or incorrectly gapped spark
plugs3. Replace or clean and re-gap spark
plugs (Refer to 8 - ELECTRICAL/
IGNITION CONTROL/SPARK PLUG -
CLEANING)
4. Worn or burned distributor rotor 4. Install new distributor rotor
5. Spark plug cables defective or
crossed5. Check for correct firing order or
replace spark plug cables. (Refer to 8 -
ELECTRICAL/IGNITION CONTROL/
SPARK PLUG CABLE - DIAGNOSIS
AND TESTING)
6. Faulty coil 6. Test and replace, if necessary (Refer
to 8 - ELECTRICAL/IGNITION
CONTROL/IGNITION COIL - REMOVAL)
7. Intake manifold vacuum leak 7. Inspect intake manifold gasket and
vacuum hoses (Refer to 9 - ENGINE/
MANIFOLDS/INTAKE MANIFOLD -
DIAGNOSIS AND TESTING).
ENGINE MISSES ON
ACCELERATION1. Worn or incorrectly gapped spark
plugs1. Replace spark plugs or clean and set
gap. (Refer to 8 - ELECTRICAL/
IGNITION CONTROL/SPARK PLUG -
CLEANING)
2. Spark plug cables defective or
crossed2. Replace or rewire secondary ignition
cables. (Refer to 8 - ELECTRICAL/
IGNITION CONTROL/SPARK PLUG
CABLE - REMOVAL)
3. Dirt in fuel system 3. Clean fuel system
4. Burned, warped or pitted valves 4. Install new valves
5. Faulty coil 5. Test and replace as necessary (Refer
to 8 - ELECTRICAL/IGNITION
CONTROL/IGNITION COIL - REMOVAL)
BR/BEENGINE 3.9L 9 - 5
ENGINE 3.9L (Continued)