diagram DODGE RAM 1999 Service Workshop Manual
[x] Cancel search | Manufacturer: DODGE, Model Year: 1999, Model line: RAM, Model: DODGE RAM 1999Pages: 1691, PDF Size: 40.34 MB
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does not display BUS OPERATIONAL, go to appropriate VEHICLE
COMMUNICATIONS article.
2) Using scan tool select BODY COMPUTER. If scan tool
displays NO RESPONSE, go to appropriate VEHICLE COMMUNICATIONS
article. If scan tool does not displays NO RESPONSE, go to next step.
3) This test is only for vehicles equipped with speed
sensitive door locks. With doors closed and unlocked drive vehicle
faster than 15 MPH. If doors lock, system is currently functioning
properly. If doors do not lock, using scan tool select ROLLING LOCKS.
Retest system.
DOORS LOCK WITH KEY IN IGNITION & LEFT DOOR OPEN
NOTE: For connector terminal identification and wiring diagrams,
see BODY CONTROL COMPUTER - INTRODUCTION article. Perform
VERIFICATION TEST VER-1A after each repair.
CAUTION: Always turn ignition switch to OFF position prior to
disconnecting or connecting any module connector.
1) Using scan tool select SYSTEM MONITORS, then CCD BUS TEST.
If scan tool displays BUS OPERATIONAL, go to next step. If scan tool
does not display BUS OPERATIONAL, go to appropriate VEHICLE
COMMUNICATIONS article.
2) Using scan tool select BODY COMPUTER. If scan tool
displays NO RESPONSE, go to appropriate VEHICLE COMMUNICATIONS
article. If scan tool does not display NO RESPONSE, go to next step.
3) Place key in ignition. Open driver's door. Lock doors from
interior lock switch. If doors locked, go to next step. If doors did
not lock, system is currently functioning correctly.
4) Using scan tool, read left door ajar status. Open and
close left door. If door ajar state changed from OPEN to CLOSED, go to
next step. If door ajar state did not change from OPEN to CLOSED, go
to OPEN LEFT DOOR AJAR CIRCUIT under DOOR AJAR SYSTEM.
5) Ensure driver's door is open. Read key-in ignition status.
If scan tool shows KEY-IN, replace Central Timer Module (CTM). CTM is
located behind right kick panel. If scan tool does not show KEY-IN, go
to next step.
6) Gain access to CTM connector C1. Do not disconnect
connector. Using an external voltmeter, measure voltage between ground
and CTM 14-pin connector C1 terminal No. 9 (Light Blue wire). If
voltage is more than 1.5 volts, repair open Light Blue wire. If
voltage is 1.5 volts or less, go to next step.
7) Turn ignition off and remove key. Measure voltage between
ground and CTM 14-pin connector C1 terminal No. 9 (Light Blue wire).
If voltage is less than 1.5 volts, replace CTM. If voltage is 1.5
volts or more, replace ignition switch.
ONE OR ALL DOORS FAILING TO LOCK FROM ONE SWITCH (ONE OR ALL
DOORS FAILING TO UNLOCK FROM ONE SWITCH)
NOTE: For connector terminal identification and wiring diagrams,
see BODY CONTROL COMPUTER - INTRODUCTION article. Perform
VERIFICATION TEST VER-1A after each repair.
CAUTION: Always turn ignition switch to OFF position prior to
disconnecting or connecting any module connector.
1) Using scan tool select SYSTEM MONITORS, then CCD BUS TEST.
If scan tool displays BUS OPERATIONAL, go to next step. If scan tool
does not display BUS OPERATIONAL, go to appropriate VEHICLE
COMMUNICATIONS article.
2) Using scan tool select BODY COMPUTER. If scan tool
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14) Connect test light to ground and probe Orange/Black wire
of door lock actuator connector. If test light illuminates while door
unlock switch is pressed, repair open Orange/Black wire between door
lock actuator and Central Timer Module (CTM). CTM is located behind
right kick panel. If test light does not illuminate while door unlock
switch is pressed, go to next step.
15) Access CTM 18-pin connector C2. Remove connector cover.
Do not disconnect connector. Using an external voltmeter, measure
voltage between ground and CTM 18-pin connector C2 terminal No. 9
(Pink/Black wire). If voltage is more than 9.5 volts while door unlock\
switch is pressed, repair open Pink/Black wire. If voltage is 9.5
volts or less while door unlock switch is pressed, replace CTM.
16) Disconnect inoperative lock switch connector. Using an
external voltmeter, measure voltage between ground and Red wire of
door lock switch connector. If voltage is more than 9.5 volts, repair
open Red wire between door lock switch connector and voltage source.
If voltage is 9.5 volts or less, go to next step.
17) Reconnect door lock switch connector. Measure voltage
between ground and backprobe Pink/Violet wire of door lock switch
connector. If voltage is more than 9.5 volts, go to next step. If
voltage is 9.5 volts or less, replace door lock switch.
18) Access CTM 18-pin connector "B". Remove connector cover.
Do not disconnect connector. Using an external voltmeter, measure
voltage between ground and CTM 18-pin connector "B" terminal No. 13
(Pink/Dark Green wire). If voltage is more than 9.5 volts, replace
CTM. If voltage is 9.5 volts or less, repair open Pink/Dark Green wire
between CTM and door lock switch.
REMOTE KEYLESS ENTRY PROBLEM
NOTE: For connector terminal identification and wiring diagrams,
see BODY CONTROL COMPUTER - INTRODUCTION article. Perform
VERIFICATION TEST VER-1A after each repair.
CAUTION: Always turn ignition switch to OFF position prior to
disconnecting or connecting any module connector.
1) Using scan tool select SYSTEM MONITORS, then CCD BUS TEST.
If scan tool displays BUS OPERATIONAL, go to next step. If scan tool
does not display BUS OPERATIONAL, go to appropriate VEHICLE
COMMUNICATIONS article.
2) Using scan tool select BODY COMPUTER. If scan tool
displays NO RESPONSE, go to appropriate VEHICLE COMMUNICATIONS
article. If scan tool does not display NO RESPONSE, go to next step.
3) Operate door locks with Remote Keyless Entry (RKE)
transmitter. If doors locked when transmitter was actuated, system is
currently functioning properly. If doors do not lock when transmitter
was actuated, go to next step.
4) Ensure transmitter battery voltage is 3.2 volts. Turn
ignition on. Place transmission in park and disarm anti-theft system.
Using scan tool, select MISCELLANEOUS, then PROGRAM RKE. If BCM IS IN
PROGRAMMING MODE does not appear, exit and select PROGRAM RKE again.
Press any transmitter button. A single chime will announce RKE module
accepted transmission. Repeat procedure for all transmitters used with
vehicle. Operate door locks from reprogrammed transmitter. If door
locks operate properly, system has been repaired. If door locks do not
operate properly, go to next step.
5) Using scan tool, reprogram a known good transmitter:
Operate door locks with reprogrammed transmitter. If doors locked
properly, replace transmitter. If doors did not lock properly, replace
CTM.
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VEHICLE THEFT/SECURITY SYSTEM
DOOR DISARM SWITCH FAILURE
NOTE: For connector terminal identification and wiring diagrams,
see BODY CONTROL COMPUTER - INTRODUCTION article. Perform
VERIFICATION TEST VER-1A after each repair.
CAUTION: Always turn ignition switch to OFF position prior to
disconnecting or connecting any module connector.
1) Using scan tool, read VTSS inputs/outputs information. If
scan tool displays door disarm switch state OPEN, system is currently
functioning properly. If scan tool does not display door disarm switch
state OPEN, go to next step.
2) Disconnect left door disarm switch. If scan tool displays
door disarm switch state OPEN, replace left door disarm switch. If
scan tool does not display door disarm switch state OPEN, go to next
step.
3) Disconnect right door disarm switch. If scan tool displays
door disarm switch state OPEN, replace left door disarm switch. If
scan tool does not display door disarm switch state OPEN, go to next
step.
4) Access Central Timer Module (CTM). CTM is located under
left side of instrument panel. Disconnect CTM 18-pin connector C2.
Using an external ohmmeter, measure resistance between ground and CTM
18-pin connector C2 terminal No. 10 (Light Green/Orange wire). If
resistance is less than 1000 ohms, repair short to ground in Light
Green/Orange wire. If resistance is 1000 ohms or more, replace CTM.
DOOR LOCK SWITCH FAILURE
NOTE: For connector terminal identification and wiring diagrams,
see BODY CONTROL COMPUTER - INTRODUCTION article. Perform
VERIFICATION TEST VER-1A after each repair.
CAUTION: Always turn ignition switch to OFF position prior to
disconnecting or connecting any module connector.
1) Clear trouble codes as needed. See BODY CONTROL COMPUTER -
INTRODUCTION article. Using scan tool, read I/O's door lock switch
status. If scan tool displays RELEASED, system is currently
functioning properly. If scan tool does not display RELEASED, go to
next step.
2) Disconnect left door lock switch connector. If scan tool
displays RELEASED, replace left door lock switch. If scan tool does
not display RELEASED, go to next step.
3) Disconnect right door lock switch connector. If scan tool
displays RELEASED, replace right door lock switch. If scan tool does
not display RELEASED, go to next step.
4) Locate Central Timer Module (CTM). CTM is located under
left side of instrument panel. Disconnect CTM 18-pin connector C2.
Using an external voltmeter, measure voltage between ground and CTM
18-pin connector C2 terminal No. 13 (Pink/Dark Green wire). If voltage\
is more than 1.5 volts, repair short to voltage in Pink/Dark Green
wire between CTM and door lock switch. If voltage is 1.5 volts or
less, replace CTM.
DOOR UNLOCK SWITCH FAILURE
NOTE: For connector terminal identification and wiring diagrams,
see BODY CONTROL COMPUTER - INTRODUCTION article. Perform
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VERIFICATION TEST VER-1A after each repair.
CAUTION: Always turn ignition switch to OFF position prior to
disconnecting or connecting any module connector.
1) Clear trouble codes as needed. See BODY CONTROL COMPUTER -
INTRODUCTION article. Using scan tool, read I/O's door unlock switch
status. If scan tool displays RELEASED, system is currently
functioning properly. If scan tool does not display RELEASED, go to
next step.
2) Disconnect left door lock switch connector. If scan tool
displays RELEASED, replace left door lock switch. If scan tool does
not display RELEASED, go to next step.
3) Disconnect right door lock switch connector. If scan tool
displays RELEASED, replace right door lock switch. If scan tool does
not display RELEASED, go to next step.
4) Locate Central Timer Module (CTM). CTM is located under
left side of instrument panel. Disconnect CTM 18-pin connector C2.
Using an external voltmeter, measure voltage between ground and CTM
18-pin connector C2 terminal No. 4 (Orange/Dark Green wire). If
voltage is more than 1.5 volts, repair short to voltage in Orange/Dark
Green wire between CTM and door lock switch. If voltage is 1.5 volts
or less, replace CTM.
IDENTIFYING VTSS PROBLEMS
NOTE: For connector terminal identification and wiring diagrams,
see BODY CONTROL COMPUTER - INTRODUCTION article. Perform
VERIFICATION TEST VER-1A after each repair.
CAUTION: Always turn ignition switch to OFF position prior to
disconnecting or connecting any module connector.
1) Using scan tool, select BODY SYSTEM then VTSS and read
Central Timer Module (CTM) DTCs. If any VTSS DTCs are displayed,
perform appropriate procedure. See VTSS DTC table. If no VTSS DTCs are
displayed, go to next step.
VTSS DTC
\
\
\
\
\
\
\
DTC Message Perform
DOOR DISARM SWITCH FAILURE .............. DOOR DISARM SWITCH FAILURE
DOOR LOCK SWITCH FAILURE .................. DOOR LOCK SWITCH FAILURE
DOOR UNLOCK SWITCH FAILURE .............. DOOR UNLOCK SWITCH FAILURE
EEPROM CHECKSUM FAILURE ................................ Replace CTM
INTERNAL ROM TEST FAILURE .............................. Replace CTM
\
\
\
\
\
\
\
2) Select VTSS then MONITORS. If scan tool displays, OK TO
RUN, NOT OK TO ARM, PCM has not recorded more than 20 starts. Start
engine 20 times and retest. If message does not change to OK TO ARM,
replace PCM. If scan tool displays NO RESPONSE TO PCM, see appropriate
VEHICLE COMMUNICATIONS article. If scan tool does not display OK TO
RUN, NOT OK TO ARM or NO RESPONSE TO PCM, go to next step.
3) Using scan tool, actuate horn, headlights and VTSS light
to flash. If horn does not sound, go to next step. If headlights do
not flash, go to step 6). If VTSS light does not flash, go to step 9).\
If all function properly, go to step 12).
4) Press horn button. If horn does not sound, go to
appropriate STEERING COLUMN SWITCHES article. If horn sounds, go to
next step.
5) Locate Central Timer Module (CTM). CTM is located behind
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disarm switch state CLOSED, replace CTM.
23) Turn ignition switch to START position. If horn does not
sound, go to next step. If horn sounds, go to step 24).
24) Locate Central Timer Module (CTM). CTM is located behind\
right kick panel. Disconnect CTM 14-pin connector C1. Using an
external voltmeter, measure voltage between ground and CTM 14-pin
connector C1 terminal No. 8 (Dark Blue/White wire). If voltage is more\
than 10 volts, replace CTM. If voltage is 10 volts or less, repair
open Dark Blue/White wire between CTM and RUN-ACC fuse in junction
block.
WINDSHIELD WIPER SYSTEM
WIPER PARK SWITCH FAILURE
NOTE: For connector terminal identification and wiring diagrams,
see BODY CONTROL COMPUTER - INTRODUCTION article. Perform
VERIFICATION TEST VER-1A after each repair.
CAUTION: Always turn ignition switch to OFF position prior to
disconnecting or connecting any module connector.
NOTE: It takes 8 seconds for wiper park switch failure DTC to set.
1) Using scan tool, clear DTCs. See appropriate SELF-
DIAGNOSTICS article. Operate wipers in low speed, then intermittent
mode. Reread DTCs. If WIPER PARK SWITCH FAILURE is displayed, go to
next step. If WIPER PARK SWITCH FAILURE is not displayed, system is
currently functioning properly.
2) Gain access to wiper motor connector. Using an external
voltmeter, measure voltage between ground and wiper motor terminal No.
2 (Dark Green wire). If voltage is more than 9 volts, go to next step.\
If voltage is 9 volts or less, replace wiper motor.
3) Locate Central Timer Module (CTM). CTM is located under
left side of instrument panel. Using an external voltmeter, measure
voltage between ground and backprobe of CTM 14-pin Green connector C1
terminal No. 11 (Dark Green wire). If voltage is 9 volts or less,
replace CTM. If voltage is more than 9 volts, repair short to voltage
in Dark Green wire between CTM and wiper relay or wiper motor.
INTERMITTENT WIPERS INOPERATIVE
NOTE: For connector terminal identification and wiring diagrams,
see BODY CONTROL COMPUTER - INTRODUCTION article. Perform
VERIFICATION TEST VER-1A after each repair.
CAUTION: Always turn ignition switch to OFF position prior to
disconnecting or connecting any module connector.
1) Using scan tool select CENTRAL TIMER MODULE. If scan tool
displays NO RESPONSE, go to appropriate VEHICLE COMMUNICATIONS
article. If scan tool displays any CCD bus failure message, go to
SYMPTOM IDENTIFICATION. If scan tool does not display NO RESPONSE or
any CCD bus failure message, go to next step.
2) If problem is wipers parking in wrong position, go to next
step. If problem is not wipers parking in wrong position, go to step
5).
3) Gain access to wiper motor connector. Turn wipers on to
low speed. Using an external voltmeter, measure voltage between ground
and wiper motor switch terminal No. 2 (Dark Green wire). If voltage
does not cycle between zero and 12 volts, replace wiper motor. If
voltage cycles between zero and 12 volts, go to next step.
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4) Locate Central Timer Module (CTM). CTM is located under
left side of instrument panel. Using an external voltmeter, measure
voltage between ground and backprobe of CTM 14-pin Green connector C1
terminal No. 11 (Dark Green wire). Wipers should be operating at low
speed. If voltage does not cycle between zero and 12 volts, repair
open Dark Green wire between CTM and wiper relay or wiper motor. If
voltage cycles between zero and 10 volts, replace CTM.
5) Using scan tool, monitor intermittent wiper voltage level.
Rotate wiper switch from low intermittent to high intermittent level.
If voltage changes from approximately 2.5 to 12 volts, replace CTM. If
voltage does not change from approximately 2.5 to 12 volts, go to next
step.
6) Disconnect 24-pin multifunction switch connector. Using an
external ohmmeter, measure resistance of White/Dark Blue wire between
multifunction switch connector terminal No. 1 and CTM 14-pin Green
connector C1 terminal No. 12. if resistance is less than 5 ohms,
replace multifunction switch. If resistance is 5 ohms or more, repair
open White/Dark Blue wire between multifunction switch and CTM.
NO WIPER ACTUATION AFTER WASH BUTTON PUSHED
NOTE: For connector terminal identification and wiring diagrams,
see BODY CONTROL COMPUTER - INTRODUCTION article. Perform
VERIFICATION TEST VER-1A after each repair.
CAUTION: Always turn ignition switch to OFF position prior to
disconnecting or connecting any module connector.
1) Using scan tool select Central Timer Module (CTM). If sca\
n
tool displays NO RESPONSE, go to appropriate VEHICLE COMMUNICATIONS
article. If scan tool displays any CCD bus failure message, go to
SYMPTOM IDENTIFICATION. If scan tool does not display NO RESPONSE or
any CCD bus failure message, go to next step.
2) Turn ignition on. If washer system works, go to next step.
If washer system does not work, see appropriate WIPER/WASHER SYSTEMS
article.
3) Using scan tool, actuate washer. If washer pump sense
displays ON, replace CTM. If washer pump sense does not display ON,
repair open Brown wire between CTM 14-pin connector C1 terminal No. 10
and multifunction switch.
WIPER SPEED SENSITIVE FEATURE INOPERATIVE
NOTE: For connector terminal identification and wiring diagrams,
see BODY CONTROL COMPUTER - INTRODUCTION article. Perform
VERIFICATION TEST VER-1A after each repair.
CAUTION: Always turn ignition switch to OFF position prior to
disconnecting or connecting any module connector.
1) Using scan tool select Central timer module (CTM). If sca\
n
tool display is not blank or have a CCD bus failure message, go to
next step. If scan tool display is blank or has a CCD bus failure
message, see appropriate VEHICLE COMMUNICATIONS article.
2) Using scan tool, select Powertrain Control Module (PCM).
If scan tool display is not blank or have a CCD bus failure message,
go to next step. If scan tool display is blank or has a CCD bus
failure message, see appropriate VEHICLE COMMUNICATIONS article.
3) Raise and support vehicle. Turn wipers on to lowest
intermittent position. Time interval between wipes. Spin rear wheels
to more than 15 MPH. If interval between wipes decreased to
approximately 18 seconds, system is currently functioning properly. If
interval between wipes did not decrease to approximately 18 seconds,
Page 385 of 1691
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
\
\
\
\
\
\
\
Switch Plunger Check Between Continuity
Position Terminals
\
\
\b \
\
\
\b \
\
Released 5 & 6 Yes
\
\
\b \
\
\
\b \
\
Depressed 1 & 2 Yes
\
\
\
\b \
\
3 & 4 Yes
\
\
\
\
\
\
\
\f
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
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10.4 volts. FTC P1595 will set if vacuum and vent solenoids do not
respond when actuated by PCM.
Possible Causes:
* Ground circuit open.
* S/C brake switch output circuit open.
* S/C power supply circuit open or shorted.
* S/C servo defective.
* S/C vacuum solenoid control circuit open or shorted.
* S/C vent solenoid control circuit open or shorted.
* Brake switch defective or out of adjustment.
* Defective PCM.
NOTE: For component locations, see COMPONENT LOCATIONS. For
connector terminal identification, see CONNECTOR
IDENTIFICATION. For wiring diagram, see WIRING DIAGRAMS.
1) Turn ignition on. Turn Speed Control (S/C) on. Using scan\
tool, actuate S/C vent solenoid. If speed control servo clicks, go to
next step. If S/C servo does not click, go to step 7).
2) Using scan tool, actuate S/C vacuum solenoid. If S/C servo
clicks, go to next step. If S/C servo does not click, go to step 6).
3) Turn ignition on. Using scan tool, actuate S/C vacuum
solenoid. Wiggle wiring harness between S/C servo and brake switch to
PCM while scan tool is still actuating speed control vacuum solenoid.
If wiggling did not cause an interruption of S/C servo actuation, go
to next step. If wiggling caused an interruption of S/C servo
actuation, repair wiring harness as necessary. Perform TEST VER-4A
under VERIFICATION TESTS.
4) Turn ignition off. Inspect S/C wiring and connectors.
Clean or repair as necessary. Perform TEST VER-4A under VERIFICATION
TESTS. If wiring and connectors are okay, go to next step.
5) Using scan tool, actuate S/C vent solenoid. Wiggle wiring
harness between S/C servo and brake switch to PCM while scan tool is
still actuating speed control vacuum solenoid. If wiggling did not
cause interruption of S/C servo actuation, test is complete. If
wiggling caused interruption of S/C servo actuation, repair wiring
harness as necessary. Perform TEST VER-4A under VERIFICATION TESTS.
6) Using scan tool, actuate S/C vent solenoid. Wiggle wiring
harness between S/C servo and brake switch to PCM while scan tool is
still actuating speed control vacuum solenoid. If wiggling did not
cause interruption of S/C servo actuation, go to next step. If
wiggling caused interruption of S/C servo actuation, repair wiring
harness as necessary. Perform TEST VER-4A under VERIFICATION TESTS.
NOTE: Ensure brake pedal is not depressed during the following
steps.
7) Turn ignition off. Disconnect S/C servo 4-pin connector.
Inspect all related wiring and connectors and repair as necessary.
Turn ignition on. Turn S/C switch on. Using a 12-volt test light,
probe brake switch output circuit at S/C servo connector terminal No.
3 (Dark Blue/Red wire). If test light is illuminated and bright, go to\
next step. If test light is dim or not illuminated, go to step 13).
8) Turn ignition off. Using an ohmmeter, check resistance of
ground circuit at S/C servo connector terminal No. 4 (Black wire). If
resistance is 5 ohms or more, repair open ground circuit. Perform TEST
VER-4A under VERIFICATION TESTS. If resistance is less than 5 ohms, go
to next step.
9) Disconnect PCM. Inspect connectors. Clean or repair as
necessary. Using an ohmmeter, measure resistance between ground and
S/C vacuum solenoid control circuit at S/C servo connector terminal
Page 393 of 1691
IDENTIFICATION. For wiring diagram, see WIRING DIAGRAMS.
1) Turn ignition on. Using scan tool, read S/C inputs. While
observing display, press S/C ON/OFF switch several times and leave on.
If scan tool displays S/C switch OFF and ON, go to next step. If scan
tool does not display OFF and ON, go to step 3).
2) Using scan tool, measure S/C switch voltage. While
observing display, wiggle wiring between S/C switch and PCM. If
voltage was more than 4.9 volts at any time during wiggling, repair
wiring as necessary. Perform TEST VER-4A under VERIFICATION TESTS. If
voltage was 4.9 volts or less during wiggling, test is complete.
3) Turn ignition off. Disconnect S/C ON/OFF switch. Inspect
connector. Clean or repair as necessary. Using an ohmmeter, measure
resistance of S/C switch ground circuit. If resistance is 5 ohms or
more, repair open ground circuit. Perform TEST VER-4A under
VERIFICATION TESTS. If resistance is less than 5 ohms, go to next
step.
4) Turn ignition on. Using a voltmeter, measure voltage on
S/C switch signal circuit. If voltage is more than 6 volts, repair
short to voltage. Perform TEST VER-4A under VERIFICATION TESTS. If
voltage is 6 volts or less, go to next step.
5) Turn ignition off. Disconnect PCM. Inspect connectors.
Clean or repair as necessary. Using an ohmmeter, measure resistance of
S/C switch signal circuit between ON/OFF switch connector and PCM
connector C3, terminal No. 32 (White/Light Green wire on Ram Van & Ram
Wagon; Red/Light Green wire on all other models). If resistance is
less than 5 ohms, go to next step. If resistance is 5 ohms or more, go
to step 7).
6) Using an ohmmeter, measure resistance across ON/OFF
switch. Resistance should be 20,300-20,700 ohms. If resistance is not
as specified, replace ON/OFF switch. Perform TEST VER-4A under
VERIFICATION TESTS. If resistance is as specified, replace PCM.
Perform TEST VER-4A under VERIFICATION TESTS.
7) Disconnect clockspring 5-pin connector. Clockspring 5-pin
connector is located behind lower steering column shroud. Inspect
connectors. Clean or repair as necessary. Using an ohmmeter, measure
resistance of S/C switch signal circuit between PCM connector C3,
terminal No. 32 and clockspring connector (White/Light Green wire on
Ram Van and Ram Wagon; Red/Light Green wire on all other models). If
resistance is 5 ohms or more, repair open circuit. Perform TEST VER-4A
under VERIFICATION TESTS. If resistance is less than 5 ohms, replace
clockspring. See appropriate AIR BAG RESTRAINT SYSTEMS article.
Perform TEST VER-4A under VERIFICATION TESTS.
FTC P1597: SPEED CONTROL SWITCH ALWAYS LOW
FTC P1597 will set if Speed Control (S/C) switch voltage is
less than 0.39 volts for 2 minutes when ignition is on and battery
voltage is more than 10.4 volts.
Possible Causes:
* S/C ON/OFF switch defective.
* S/C RESUME/ACCEL switch defective.
* S/C switch signal circuit shorted to ground.
* Defective PCM.
* Defective clockspring.
NOTE: For component locations, see COMPONENT LOCATIONS. For
connector terminal identification, see CONNECTOR
IDENTIFICATION. For wiring diagram, see WIRING DIAGRAMS.
1) Turn ignition on. Using scan tool, read S/C switch
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voltage. If voltage is less than one volt, go to next step. If voltage
is one volt or more, condition to set FTC is not present at this time.
Test is complete.
2) While observing scan tool, disconnect S/C ON/OFF switch.
If S/C switch voltage changes to 5 volts, replace S/C ON/OFF switch.
Perform TEST VER-4A under VERIFICATION TESTS. If voltage does not
change to 5 volts, go to next step.
3) While observing scan tool, disconnect S/C RESUME/ACCEL
switch. If S/C switch voltage changes to 5 volts, replace S/C
RESUME/ACCEL switch. Perform TEST VER-4A under VERIFICATION TESTS. If
voltage does not change to 5 volts, go to next step.
4) Turn ignition off. Ensure both S/C switches are still
disconnected. Using an ohmmeter, check resistance between S/C switch
connector terminals (S/C switch signal circuit and S/C switch ground
circuit). If resistance is less than 5 ohms, repair short circuit.
Perform TEST VER- 4A under VERIFICATION TESTS. If resistance is 5 ohms
or more, go to next step.
5) Disconnect clockspring 4-pin connector. Clockspring 4-pin
connector is located behind steering wheel. Inspect connector. Clean
or repair as necessary. Using an ohmmeter, check resistance between
ground and S/C switch signal circuit at clockspring connector (Dark
Green/Red wire on all models except Ram Van and Ram Wagon; wire color
is not available for Ram Van and Ram Wagon). If resistance is less
than 5 ohms, repair short to ground. Perform TEST VER-4A under
VERIFICATION TESTS. If resistance is 5 ohms or more, go to next step.
6) Disconnect PCM. Inspect connectors. Clean or repair as
necessary. Using an ohmmeter, check resistance between ground and S/C
switch signal circuit at either S/C switch connector (Dark Green/Red
wire on all models except Ram Van and Ram Wagon; wire color is not
available for Ram Van and Ram Wagon). If resistance is less than 5
ohms, repair short to ground. Perform TEST VER-4A under VERIFICATION
TESTS. If resistance is 5 ohms or more, replace PCM. Perform TEST VER-
4A under VERIFICATION TESTS.
FTC P1683: SPEED CONTROL POWER RELAY CIRCUIT
FTC P1683 will set if Speed Control (S/C) power supply
circuit is open or shorted when S/C is turned on.
Possible Causes:
* Brake switch out of adjustment.
* S/C brake switch output circuit open or shorted.
* Defective S/C servo.
* Defective brake switch.
* S/C vacuum or vent solenoid control circuits open or
shorted.
* Defective PCM.
* Ground circuit open.
* S/C power supply circuit open.
NOTE: For component locations, see COMPONENT LOCATIONS. For
connector terminal identification, see CONNECTOR
IDENTIFICATION. For wiring diagram, see WIRING DIAGRAMS.
NOTE: Ensure brake pedal is not depressed during the following
steps.
1) Turn ignition off. Disconnect S/C servo connector. Inspect
connector. Clean or repair as necessary. Turn ignition on. Using scan
tool, actuate S/C relay. Using a 12-volt test light, probe S/C brake
switch output circuit at S/C servo connector terminal No. 3 (Dark
Blue/Red wire). If test light is illuminated and bright, go to next