1999 DODGE RAM Ignition

scan tool displayed P/N and D/R in correct positions, go to next step.
4) Raise drive wheels and support vehicle, allowing wheels to
spin. Using scan tool, erase DTCs. Start engine. Using scan tool, read
Output Speed Sensor (OSS). Shift transmission into first gear. While
observing scan tool, allow wheels to spin at a speed less than 15 MPH.
If scan tool displays OSS more than 60 RPM, go to next step. If scan
tool displays OSS 60 RPM or less, go to step 7).
5) While wheels are spinning, wiggle wiring between OSS and
PCM. If OSS reading dropped while wiggling, repair intermittent short
or open circuit. Perform TEST VER-5A under VERIFICATION TESTS. If OSS
reading did not drop, go to next step.
6) Using scan tool, erase DTCs. Road test vehicle. Read DTCs.
If FTC P0720 returns, replace PCM. Perform TEST VER-5A under
VERIFICATION TESTS. If FTC P0720 did not return, go to step 13).
7) Turn ignition off. Disconnect PCM. Inspect connectors.
Clean or repair as necessary. Using an ohmmeter, measure resistance
between ground and OSS signal circuit at PCM connector C2, terminal
No. 28 (Light Green/Black wire on Ram Pickup; Light Green/White wire
on all other models). If resistance is less than 5 ohms, repair short
to ground. Perform TEST VER-5A under VERIFICATION TESTS.
8) Using an ohmmeter, measure resistance between ground and
OSS ground circuit at PCM connector C2, terminal No. 25 (Dark
Blue/Black wire). If resistance is less than 5 ohms, repair short to
ground. Perform TEST VER-5A under VERIFICATION TESTS. If resistance is
5 ohms or more, go to next step.
9) Disconnect OSS. Using an ohmmeter, measure resistance
across OSS terminals. If resistance is not 300-1200 ohms, replace OSS.
Perform TEST VER-5A under VERIFICATION TESTS. If resistance is 300-
1200 ohms, go to next step.
10) Using an ohmmeter, measure resistance of OSS signal
circuit between PCM connector C2, terminal No. 28 and OSS connector
(Light Green/Black wire on Ram Pickup; Light Green/White wire on all
other models). If resistance is more than 5 ohms, repair open circuit.
Perform TEST VER-5A under VERIFICATION TESTS. If resistance is 5 ohms
or less, go to next step.
11) Using an ohmmeter, measure resistance of OSS ground
circuit between PCM connector C2, terminal No. 25 and OSS connector
(Dark Blue/Black wire). If resistance is more than 5 ohms, repair open\
circuit. Perform TEST VER-5A under VERIFICATION TESTS. If resistance
is 5 ohms or less, go to next step.
12) Reconnect OSS. Using an ohmmeter, measure resistance
between PCM connector C2, terminals No. 25 (Dark Blue/Black wire) and
No. 28 (Light Green/Black wire on Ram Pickup; Light Green/White wire
on all other models). If resistance is 300-1200 ohms, replace PCM.
Perform TEST VER-5A under VERIFICATION TESTS. If resistance is not
300-1200 ohms, go to next step.
13) Inspect wiring and connectors. repair as necessary.
Perform TEST VER-5A under VERIFICATION TESTS. If wiring and connectors
are okay, go to next step.
14) Conditions required to set FTC are not present at this
time. Check freeze frame data to determine conditions when FTC was
set. Raise drive wheels and support vehicle, allowing wheels to spin.
Using scan tool, read OSS. Shift transmission into first gear. While
observing scan tool, allow wheels to spin at a speed less than 15 MPH.
Wiggle wiring between OSS and PCM. If OSS reading dropped while
wiggling, repair intermittent short or open circuit. Perform TEST VER-
5A under VERIFICATION TESTS. If OSS reading did not drop, no problem
is indicated at this time.
FTC P1595: SPEED CONTROL SOLENOID CIRCUITS
Speed Control (S/C) solenoid circuits are monitored when
engine is running, S/C switch is on and battery voltage is more than

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

No. 1 (Tan/Red wire). 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.
10) Using an ohmmeter, check resistance between ground and
S/C vent solenoid control circuit at S/C servo connector terminal No.
2 (Light Green/Red wire). 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.
11) Using an ohmmeter, measure resistance of S/C vacuum
solenoid control circuit between S/C servo connector terminal No. 1
and PCM connector C3, terminal No. 4 (Tan/Red wire). If resistance is
5 ohms or more, repair open circuit. Perform TEST VER-4A under
VERIFICATION TESTS. If resistance is less than 5 ohms, go to next
step.
12) Using an ohmmeter, check resistance of S/C vent solenoid
control circuit between S/C servo connector terminal No. 2 and PCM
connector C3, terminal No. 5 (Light Green/Red wire). 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 S/C
servo. Perform TEST VER-4A under VERIFICATION TESTS.
13) Using an ohmmeter, check resistance between ground and
brake switch output circuit at S/C servo connector terminal No. 3
(Dark Blue/Red wire). 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.
14) Reconnect PCM. Disconnect brake switch connector. Turn
ignition on. Turn S/C on. Using a 12-volt test light, probe S/C power
supply circuit at brake switch connector terminal No. 3 (Yellow/Red
wire). If test light is illuminated and bright, go to next step. If
test light is not illuminated or dim, go to step 17).
15) Turn ignition off. Using an ohmmeter, check resistance of
S/C brake switch output circuit between S/C servo connector terminal
No. 3 and brake switch connector terminal No. 4 (Dark Blue/Red wire).
If resistance is 5 ohms or more, repair open circuit. Perform TEST
VER-4A under VERIFICATION TESTS. If resistance is less than 5 ohms, go
to next step.
16) Check brake switch adjustment. See BRAKE SWITCH under
REMOVAL & INSTALLATION. Adjust as necessary. Perform TEST VER- 4A
under VERIFICATION TESTS. If brake switch adjustment is okay, replace
brake switch. Perform TEST VER-4A under VERIFICATION TESTS.
17) Turn ignition off. Disconnect PCM. Inspect connectors.
Clean or repair as necessary. Using an ohmmeter, measure resistance of
S/C power supply circuit between PCM connector C3, terminal No. 11 and
brake switch connector terminal No. 3 (Yellow/Red wire). 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 PCM.
Perform TEST VER-4A under VERIFICATION TESTS.
FTC P1596: SPEED CONTROL SWITCH ALWAYS HIGH
FTC P1596 will set if an open circuit is detected in Speed
Control (S/C) switch circuit when ignition is on.
Possible Causes:
* Defective clockspring.
* S/C switch ground circuit open.
* Defective ON/OFF switch.
* Defective PCM.
* S/C switch signal circuit open or shorted to voltage.
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 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

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

step. If test light is dim or not illuminated, go to step 7).
2) 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.
3) Disconnect PCM. Inspect connectors. Clean or repair as
necessary. Using an ohmmeter, measure resistance of S/C vacuum
solenoid control circuit between PCM connector C3, terminal No. 4 and
S/C servo connector terminal No. 1 (Tan/Red wire). If resistance is 5
ohms or more, repair open circuit. Perform TEST VER-4A under
VERIFICATION TESTS. If resistance is less than 5 ohms, go to next
step.
4) Using an ohmmeter, check resistance between ground and S/C
vacuum solenoid control circuit at S/C servo connector terminal No. 1
(Tan/Red wire). 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.
5) Using an ohmmeter, check resistance of S/C vent solenoid
control circuit between PCM connector C3, terminal No. 5 and S/C servo
connector terminal No. 2 (Light Green/Red wire). If resistance is 5
ohms or more, repair open circuit. Perform TEST VER-4A under
VERIFICATION TESTS. If resistance is less than 5 ohms, go to next
step.
6) Using an ohmmeter, check resistance between ground and S/C
vent solenoid control circuit at S/C servo connector terminal No. 2
(Light Green/Red wire). 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 S/C servo. Perform TEST VER-4A
under VERIFICATION TESTS.
7) Turn ignition off. Disconnect brake switch connector.
Inspect connectors. Clean or repair as necessary. Turn ignition on.
Using scan tool, actuate S/C solenoid. Using a 12-volt test light,
probe S/C power supply circuit at brake switch connector terminal No.
4 (Yellow/Red wire). If test light is illuminated and bright, go to
next step. If test light is not illuminated or dim, go to step 10).
8) Check brake switch adjustment. See BRAKE SWITCH under
REMOVAL & INSTALLATION. Adjust as necessary. Perform TEST VER- 4A
under VERIFICATION TESTS. If brake switch adjustment is okay, go to
next step.
9) Using an ohmmeter, check resistance of brake switch output
circuit between brake switch connector terminal No. 3 and S/C servo
connector terminal No. 3 (Dark Blue/Red wire). If resistance is more
than 5 ohms, repair open circuit. Perform TEST VER-4A under
VERIFICATION TESTS. If resistance is 5 ohms or less, replace brake
switch. Perform TEST VER-4A under VERIFICATION TESTS.
10) Turn ignition off. Using an ohmmeter, check resistance
between ground and S/C brake switch output circuit at S/C servo
connector terminal No. 3 (Dark Blue/Red wire). 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.
11) Disconnect PCM. Inspect connectors. Clean or repair as
necessary. Using an ohmmeter, check resistance of S/C power supply
circuit between PCM connector C3, terminal No. 11 and brake switch
connector terminal No. 4 (Yellow/Red wire). 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 PCM. Perform TEST
VER-4A under VERIFICATION TESTS.
FTC P1899: PARK/NEUTRAL POSITION (PNP) SWITCH STUCK IN PARK
OR IN GEAR (A/T MODELS)
Possible Causes:

* PNP switch defective.
* PNP switch sense circuit open or shorted.
* PNP switch stuck.
* PCM defective.
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 PNP switch state.
While observing scan tool, move gear selector between Park and
Reverse. If scan tool displays P/N and D/R, go to next step. If scan
tool does not display P/N and D/R, go to step 3).
2) Turn ignition off. Inspect wiring and connectors related
to PNP switch. Repair as necessary. Perform TEST VER-5A under
VERIFICATION TESTS. If wiring and connectors are okay, condition to
set FTC is not present at this time. Test is complete. Use freeze
frame data to determine conditions when FTC was set.
3) Turn ignition off. Disconnect PCM. Inspect connectors.
Clean or repair as necessary. Using an ohmmeter, check resistance
between ground and PNP switch sense circuit at PCM connector C1,
terminal No. 6 (Black/White wire). While observing ohmmeter, move gear\
selector from Park to Reverse and back to Park. If resistance switched
from less than 10 ohms to more than 10 ohms, replace PCM. Perform TEST
VER-5A under VERIFICATION TESTS. If resistance was less than 10 ohms
at all times, go to next step. If resistance was more than 10 ohms at
all times, go to step 5).
4) Disconnect PNP switch. Inspect connectors. Clean or repair
as necessary. Using an ohmmeter, check resistance between ground and
PNP switch sense circuit. If resistance is less than 5 ohms, repair
short to ground. Perform TEST VER-5A under VERIFICATION TESTS. If
resistance is 5 ohms or more, repair or replace stuck PNP switch.
Perform TEST VER-5A under VERIFICATION TESTS.
5) Using an ohmmeter, check resistance of PNP switch circuit
between PNP switch connector and PCM connector C1, terminal No. 6
(Black/White wire). If resistance is 5 ohms or more, repair open
circuit. Perform TEST VER-5A under VERIFICATION TESTS. If resistance
is less than 5 ohms, replace PNP switch. Perform TEST VER-5A under
VERIFICATION TESTS.
SYSTEM TESTS
NOTE: For component locations, See COMPONENT LOCATIONS. For
connector terminal identification, see CONNECTOR
IDENTIFICATION. For wiring diagram, see WIRING DIAGRAMS.
CHECKING SPEED CONTROL OPERATION
NOTE: Perform this test only if there are no DTCs.
1) Turn ignition on. Using scan tool, monitor S/C switch
inputs. Press S/C ON/OFF switch several times. If scan tool displays
speed control switch on and off, go to next step. If scan tool does
not display speed control switch on and off, go to NTC-3: SPEED
CONTROL ON/OFF SWITCH.
2) While observing scan tool, press RESUME/ACCEL switch
several times. If scan tool displays RESUME/ACCEL switch PRESSED and
RELEASED, go to next step. If scan tool does not display PRESSED and
RELEASED, go to NTC-4: SPEED CONTROL RESUME/ACCEL SWITCH.
3) While observing scan tool, press brake pedal several
times. If scan tool displays brake pedal PRESSED and RELEASED, go to

next step. If scan tool does not display brake pedal PRESSED and
RELEASED, go to NTC-1: BRAKE SWITCH SENSE.
4) Turn S/C on. On A/T models, move gear selector to Drive.
If scan tool displays park neutral switch D/R, go to next step. If
scan tool does not display park neutral switch D/R, go to FTC P1899:
PARK/NEUTRAL POSITION SWITCH STUCK IN PARK OR IN GEAR under DIAGNOSTIC
TESTS.
5) On all models, using scan tool, actuate S/C vent solenoid.
Using a 12-volt test light, backprobe 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 step. If test light is dim
or is not illuminated, go to NTC-1: BRAKE SWITCH SENSE.
6) Start engine and let idle for one minute. Turn engine off.
Turn ignition on (engine off). Using scan tool, actuate S/C servo
solenoids. If throttle opens and closes, go to NTC-2: CHECKING FOR
SPEED CONTROL DENIED MESSAGE. If throttle does not open and close,
inspect throttle cable and linkage. Check vacuum supply. See VACUUM
SUPPLY under COMPONENT TESTS. Repair as necessary. Perform TEST VER-4A
under VERIFICATION TESTS.
7) While observing scan tool, press CANCEL switch several
times. If scan tool displays PRESSED and RELEASED, go to next step. If
scan tool does not display PRESSED and RELEASED, replace CANCEL
switch. Perform TEST VER-4A under VERIFICATION TESTS.
8) Turn ignition off. Disconnect S/C servo connector. 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) Reconnect S/C servo connector. Turn ignition and S/C on.
While observing scan tool, press SET switch several times. If scan
tool displays PRESSED and RELEASED, go to next step. If scan tool does
not display PRESSED and RELEASED, replace SET switch. Perform TEST
VER-4A under VERIFICATION TESTS.
10) Turn ignition off. Disconnect S/C servo connector.
Inspect terminals. If any terminal is damaged, pushed out or miswired,
repair as necessary. Perform TEST VER-4A under VERIFICATION TESTS. If
terminals are okay, go to next step.
11) Disconnect S/C servo connector. Disconnect PCM
connectors. Inspect connectors. Clean or repair as necessary. Using an
ohmmeter, check resistance of S/C vacuum solenoid control circuit
between PCM connector C3, terminal No. 4 and S/C servo connector
terminal No. 1 (Tan/Red wire). If resistance is 5 ohms or more, repair\
open circuit. Perform TEST VER-4A under VERIFICATION TESTS. If
resistance is less than 5 ohms, go to next step.
12) Turn S/C on. While observing scan tool, press COAST
switch several times. If scan tool displays PRESSED and RELEASED, go
to next step. If scan tool does not display PRESSED and RELEASED,
replace COAST switch. Perform TEST VER-4A under VERIFICATION TESTS.
13) Using an ohmmeter, check resistance of S/C vent solenoid
control circuit between PCM connector C3, terminal No. 5 and S/C servo
connector terminal No. 2 (Light Green/Red wire). 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 S/C
servo. Perform TEST VER-4A under VERIFICATION TESTS.
NTC-1: BRAKE SWITCH SENSE
Possible Causes:
* Ground circuit open.
* Defective brake switch.
* Brake switch sense circuit open or shorted.
* Defective PCM.