Symptom:
SPEED CONTROL ON/OFF SWITCH
POSSIBLE CAUSES
CLOCKSPRING DEFECTIVE
PCM DEFECTIVE (SPEED CONTROL ON/OFF/SET SWITCH)
SPEED CONTROL GROUND CIRCUIT TO SWITCH OPEN
SPEED CONTROL ON/OFF SWITCH DEFECTIVE
SPEED CONTROL ON/OFF SWITCH SIGNAL CIRCUIT OPEN
SPEED CONTROL ON/OFF SWITCH SIGNAL CIRCUIT SHORT TO GROUND
SPEED CONTROL ON/OFF SWITCH TERMINAL DAMAGED
TEST ACTION APPLICABILITY
1 Ignition on, engine not running.
With the DRBIII, monitor the Speed Control Switch inputs.
While observing the display, press the Speed Control ªONº switch.
Does the DRBIII show S/C on/off ªONº?All
Ye s®Test Complete.
Perform Powertrain Verification Test VER-4A.
No®Go To 2
2 Ignition Off
Disconnect the Speed Control On/Off and Set Switch.
Note: Check connectors - Clean/repair as necessary.
Is any terminal damaged, pushed out or miswired?All
Ye s®Repair as necessary.
Perform Powertrain Verification Test VER-4A.
No®Go To 3
3 Ignition Off
Disconnect the Speed Control On/Off and Set Switch.
Note: Check connectors - Clean/repair as necessary.
Using an Ohmmeter, measure the resistance of the S/C Ground Circuit at the S/C
ON/OFF, SET Switch Connector.
Is the resistance below 5.0 ohms?All
Ye s®Go To 4
No®Repair the open Speed Control Ground Circuit to Switch.
Perform Powertrain Verification Test VER-4A.
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SPEED CONTROL
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TEST ACTION APPLICABILITY
4 Ignition Off
Disconnect the Speed Control On/Off and Set Switch.
Note: Check connectors - Clean/repair as necessary.
Connect a jumper wire across the S/C Sw Signal Circuit to Ground Circuit.
Ignition On, Engine Not Running.
With the DRBIII, read the S/C Switch voltage.
Does the DRBIII display 0.00 volts?All
Ye s®Replace the S/C ON/OFF and SET Switch.
Perform Powertrain Verification Test VER-4A.
No®Go To 5
5 Ignition Off
Disconnect the Speed Control On/Off and Set Switch.
Note: Check connectors - Clean/repair as necessary.
Using an Ohmmeter, measure the resistance of the S/C Switch Signal at the S/C
ON/OFF, SET Switch Connector to ground.
Is the resistance below 5.0 ohms?All
Ye s®Repair the Speed Control Switch Signal Circuit for a short to
ground.
Perform Powertrain Verification Test VER-4A.
No®Go To 6
6 Ignition Off
Disconnect the Powertrain Control Module.
Disconnect the Clockspring 4±way to I/P Harness.
Note: Check connectors - Clean/repair as necessary.
Using an ohmmeter, test the S/C Switch Signal Circuit, Clockspring to PCM.
Is the resistance below 5.0 ohms?All
Ye s®Go To 7
No®Repair the open Speed Control Switch Signal Circuit.
Perform Powertrain Verification Test VER-4A.
7 Ignition Off
Disconnect the Speed Control On/Off and set Switch.
Disconnect the Powertrain Control Module.
Note: Check connectors - Clean/repair as necessary.
Using an ohmmeter, measure the S/C Switch Signal Ckt, Switch to PCM.
Is the resistance below 5.0 ohms?All
Ye s®Replace the Powertrain Control Module.
Perform Powertrain Verification Test VER-4A.
No®Go To 8
8 If there are no potential causes remaining, the Clockspring is assumed to be
defective.
View repair options.All
Repair
Replace the Clockspring.
Perform Powertrain Verification Test VER-4A.
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SPEED CONTROL
SPEED CONTROL ON/OFF SWITCH ÐContinued
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Symptom:
* CHECKING SPEED CONTROL OPERATION
POSSIBLE CAUSES
BRAKE SWITCH DEFECTIVE
GROUND CIRCUIT OPEN
S/C BRAKE SWITCH OUTPUT CIRCUIT SHORTED TO GROUND
SPEED CONTROL BRAKE SWITCH OUTPUT SUPPLY CKT OPEN
SPEED CONTROL ON/OFF/SET SWITCH DEFECTIVE
SPEED CONTROL POWER SUPPLY CIRCUIT OPEN
SPEED CONTROL POWER SUPPLY CIRCUIT SHORTED/GROUND
SPEED CONTROL SERVO CONNECTOR OBSERVABLE DEFECT
SPEED CONTROL SWITCH DEFECTIVE
CLOCK SPRING DEFECTIVE
SPEED CONTROL SERVO DEFECTIVE
SPEED CONTROL THROTTLE CABLE DEFECTIVE
SPEED CONTROL VACUUM SUPPLY LEAKS OR RESTRICTED
PCM DEFECTIVE (SPEED CONTROL OPERATION)
VACUUM RESERVOIR DEFECTIVE
TEST ACTION APPLICABILITY
1 Ignition On, Engine Not Running
With the DRB, monitor the Speed Control Switch inputs.
While observing display, press the Speed Control ON/OFF switch.
Does the DRB show S/C ON/OFF switch9ON9?All
Ye s®Go To 2
No®Refer to symptom SPEED CONTROL ON/OFF SWITCH in the
SPEED CONTROL category.
2 Ignition On, Engine Not Running
Press the S/C ON/OFF button to select S/C ªON.º
With the DRB, monitor the Speed Control Switch inputs.
While observing the DRB, press the ACCEL/RESUME/CANCEL and DECEL
switches several times.
Do all of the Switches toggle correctly between pressed and released?All
Ye s®Go To 3
No®Go To 25
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SPEED CONTROL
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TEST ACTION APPLICABILITY
3 Ignition On, Engine Not Running
Press the S/C ON/OFF button to select S/C ªON.º
With the DRB, monitor the Speed Control Switch inputs.
While observing display, press the Set Switch several times.
Does the DRB show the Set Switch pressed and released?All
Ye s®Go To 4
No®Replace the Speed Control On/Off/Set Switch.
Perform Powertrain Verification Test VER-4A.
4 Ignition On, Engine Not Running
With the DRB, monitor the Speed Control Switch inputs.
While observing display, press the Brake Pedal several times.
Does the DRB show Brake Switch Status change between pressed and released?All
Ye s®Go To 5
No®Refer to symptom SPEED CONTROL BRAKE SWITCH OUT-
PUT in the SPEED CONTROL category.
5 Ignition On, Engine Not Running
With the DRB, monitor the Speed Control Switch inputs.
While observing the display, move the Gear Selector to Drive.
Does the DRB show the Park/Neutral Switch in D/R?All
Ye s®Go To 6
No®Refer to symptom CHECKING PARK/NEUTRAL POS SWITCH
in the SPEED CONTROL category.
6 Ignition Off
Disconnect the Speed Control Servo Connector.
Note: Check connectors - Clean/repair as necessary.
Turn the Ignition on and the S/C on.
Using a Voltmeter measure voltage of the S/C Brake Switch Output Ckt at Servo
Conn.
Is the voltage above 10 volts?All
Ye s®Go To 7
No®Go To 14
7 Ignition Off
Start engine, allow to idle 1 minute.
Turn Engine off, (Ignition on).
With the DRB, actuate the Speed Control Servo Solenoids.
Does the Throttle open and close?All
Ye s®Refer to symptom SPEED CONTROL DENIED MESSAGE in the
SPEED CONTROL category.
No®Go To 8
8 Ignition Off
Inspect the Speed Control Throttle Cable.
Is the Cable disconnected or damaged?All
Ye s®Repair as necessary.
Perform Powertrain Verification Test VER-4A.
No®Go To 9
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SPEED CONTROL
* CHECKING SPEED CONTROL OPERATION ÐContinued
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TEST ACTION APPLICABILITY
9 Ignition Off
Disconnect the Vacuum Supply to the Speed Control Servo.
Attach a Vacuum Gauge to the disconnected hose.
Start engine.
Does the Vacuum Gauge read Manifold Vacuum?All
Ye s®Go To 10
No®Repair the Vacuum Supply for a leak or restriction.
Perform Powertrain Verification Test VER-4A.
10 Ignition Off
Disconnect the Speed Control Servo Connector.
Note: Check connectors - Clean/repair as necessary.
Using an Ohmmeter measure the Ground Circuit from Servo Connector to gnd.
Is the resistance below 5.0 ohms?All
Ye s®Go To 11
No®Repair the open Ground Circuit.
Perform Powertrain Verification Test VER-4A.
11 Ignition Off
Disconnect the Speed Control Servo Connector.
Note: Check connectors - Clean/repair as necessary.
Is any Terminal damaged, pushed out or miswired?All
Ye s®Repair as necessary.
Perform Powertrain Verification Test VER-4A.
No®Go To 12
12 Disconnect the vacuum supply from the Speed Control Servo.
Attach a vacuum gauge to the vacuum hose.
Start the Engine, allow to idle for 1 minute.
Turn engine off.
Observe Vacuum Gauge for 10 seconds.
Does the Vacuum hold for at least 10 seconds?All
Ye s®Go To 13
No®Replace the Vacuum Reservoir.
Perform Powertrain Verification Test VER-4A.
13 If there are no potential causes remaining, the S/C Servo is assumed to be defective.
View repair options.All
Repair
Replace the Speed Control Servo.
Perform Powertrain Verification Test VER-4A.
14 Ignition Off
Disconnect the Speed Control Servo Connector.
Note: Check connectors - Clean/repair as necessary.
Using an Ohmmeter measure the Ground Circuit from Servo Connector to gnd.
Is the resistance below 5.0 ohms?All
Ye s®Go To 15
No®Repair the open Ground Circuit.
Perform Powertrain Verification Test VER-4A.
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SPEED CONTROL
* CHECKING SPEED CONTROL OPERATION ÐContinued
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TEST ACTION APPLICABILITY
25 Ignition On.
With the DRB Select ªInputs/Outputsº, monitor the S/C Switch.
Press and hold each switch to see change in the parameter.
Does the parameter change for each switch?All
Ye s®Go To 26
No®Replace the S/C Switch.
Perform Powertrain Verification Test VER-4A.
26 Ignition On, Engine Not Running
With the DRB, monitor the Speed Control Switch inputs.
While observing display, press the Set Switch several times.
Does the DRB show the Set Switch pressed and released?All
Ye s®Go To 27
No®Replace the Speed Control On/Off/Set Switch.
Perform Powertrain Verification Test VER-4A.
27 If there are no potential causes remaining, the Clock Spring is assumed to be
defective.
View repair options.All
Repair
Replace Clock Spring.
Perform Powertrain Verification Test VER-4A.
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SPEED CONTROL
* CHECKING SPEED CONTROL OPERATION ÐContinued
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TEST ACTION APPLICABILITY
9 Ignition Off.
Connect the DRB to a functional Data Link Connector on another vehicle.
Turn the ignition on.
With the DRB, attempt to read trouble codes.
Did the DRB display ªNo Responseº?All
Ye s®Go To 10
No®Replace the initial vehicle's Powertrain Control Module.
Perform Powertrain Verification Test VER-1A.
10 Ignition Off.
Substitute another DRB Adapter Cable.
Ignition on, Engine not running.
With the DRB, attempt to read trouble codes.
Did the DRB display ªNo Responseº?All
Ye s®Go To 11
No®Replace the DRB Adapter Cable.
Perform Powertrain Verification Test VER-1A.
11 If there are no potential causes remaining, the Diagnostic Readout Box is assumed to
be defective.
View repair options.All
Repair
Have the DRB repaired or replaced.
Perform Powertrain Verification Test VER-1A.
12 Ignition Off.
Disconnect the TP Sensor Connector.
Note: Check connector-Clean/repair as necessary.
Turn the ignition on.
With a voltage, measure the Throttle Position Sensor 5±volt Supply circuit.
Is the voltage above 6.0 volts?All
Ye s®Repair the open grounds at the Powertrain Control Module
Cavities 10 and 50.
Perform the Powertrain Verification Test VER-1A
No®Go To 13
13 Ignition Off.
Disconnect the Powertrain Control Module.
Note: Check connector-Clean/repair as necessary.
Turn the ignition on.
With a voltmeter, measure Fused Ignition Switch Output Circuit.
Is the voltage above 10.0 volts?All
Ye s®Go To 14
No®Repair the open Fused Ignition Switch Output Circuit (check
Ignition Switch Fuse in PDC).
Perform Powertrain Verification Test VER-1A.
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STARTING
*(NO RESPONSE(CONDITION ÐContinued
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Symptom:
* CHECKING THE CAM AND CRANK SENSORS
POSSIBLE CAUSES
SECONDARY INDICATORS PRESENT
TEST ACTION APPLICABILITY
1 Ignition On, Engine Not Running
Note: Address all trouble codes before continuing.
Note: Ensure PCM Connectors are secure.
With the DRB, read the secondary indicators while cranking the engine.
Were there any secondary indicators present while cranking the engine?All
Ye s®Refer to Symptom list for further diagnostic test.
No®Go To 2
2 Ignition On, Engine Not Running
With the DRB in Input/Output display, monitor the current CMP and CKP states.
Crank the engine for at least 15 seconds.
Does the DRB show current CKP state9present9while cranking?All
Ye s®Go To 3
No®Refer to symptom P-0340 NO CRANK REFERENCE SIGNAL AT
PCM in the DRIVEABILITY category.
3 Ignition On, Engine Not Running
With the DRB in Input/Output display, monitor the current CMP and CKP states.
Crank the engine for at least 15 seconds.
Does the DRB show current CMP state9present9while cranking?All
Ye s®Refer to symptom * CHECKING THE SECONDARY IGNITION
SYSTEM in the STARTING category.
No®Refer to symptom P-0340 NO CAM SIGNAL AT PCM in the
DRIVEABILITY category.
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STARTING
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