Page 3993 of 4284

TEST ACTION APPLICABILITY
3 Turn the ignition off.
Disconnect the PCM harness connector.
Disconnect the IPM C4 harness connector
Measure the resistance of the ASD Output circuit between the IPM harness
connector and the PCM harness connector.
Is the resistance below 5.0 ohms.All
Ye s®Go To 4
No®Repair the ASD Relay Output circuit for an open.
Perform POWERTRAIN VERIFICATION TEST VER - 5.
4 If there are no possible causes remaining, view repair. All
Repair
Replace and program the Powertrain Control Module in accor-
dance with the Service Information.
Perform POWERTRAIN VERIFICATION TEST VER - 5.
5 Turn the ignition off.
Install a substitute relay in place of the ASD Relay.
Attempt to start the engine.
With the DRBIIIt, read DTCs.
Does the DTC reset?All
Ye s®Go To 6
No®Replace the ASD Relay.
Perform POWERTRAIN VERIFICATION TEST VER - 5.
6 Turn the ignition off.
Remove the ASD Relay from the IPM.
Using a 12-volt test light connected to ground, probe the Fused B+ circuit in the IPM.
Does the test light illuminate?All
Ye s®Go To 7
No®Replace the IPM Fuse & Relay Center.
Perform POWERTRAIN VERIFICATION TEST VER - 5.
7 Turn the ignition off.
Remove the ASD Relay from the IPM.
Disconnect the PCM harness connector.
Disconnect the IPM C4 harness connector.
Measure the resistance of the ASD Relay Output circuit between the IPM harness
connector and the PCM harness connector.
Is the resistance below 5.0 ohms.All
Ye s®Go To 8
No®Repair the ASD Relay Output circuit for an open.
Perform POWERTRAIN VERIFICATION TEST VER - 5.
199
DRIVEABILITY - GAS
P1389-NO ASD RELAY OUTPUT VOLTAGE AT PCM ÐContinued
Page 3994 of 4284

TEST ACTION APPLICABILITY
8NOTE: Ensure the IPM C4 harness connector is connected to the IPM.
Turn the ignition off.
Disconnect the PCM harness connector.
Measure the resistance of the ASD Relay Output circuit between the IPM and the
PCM harness connector.
Is the resistance below 5.0 ohms?All
Ye s®Replace and program the Powertrain Control Module in accor-
dance with the Service Information.
Perform POWERTRAIN VERIFICATION TEST VER - 5.
No®Replace the IPM Fuse & Relay Center.
Perform POWERTRAIN VERIFICATION TEST VER - 5.
9WARNING: WHEN THE ENGINE IS OPERATING, DO NOT STAND IN A
DIRECT LINE WITH THE FAN. DO NOT PUT YOUR HANDS NEAR THE
PULLEYS, BELTS OR FAN. DO NOT WEAR LOOSE CLOTHING.
NOTE: The conditions that set the DTC are not present at this time. The
following list may help in identifying the intermittent condition.
With the engine running at normal operating temperature, monitor the DRB
parameters related to the DTC while wiggling the wiring harness. Check for the
engine stumble, stall or quite running.
Refer to any Technical Service Bulletins (TSB) that may apply.
Visually inspect the related wiring harness. Look for any chafed, pierced, pinched, or
partially broken wires.
Visually inspect the related wiring harness connectors. Look for broken, bent, pushed
out, or corroded terminals.
Were any of the above conditions present?All
Ye s®Repair as necessary
Perform POWERTRAIN VERIFICATION TEST VER - 5.
No®Test Complete.
200
DRIVEABILITY - GAS
P1389-NO ASD RELAY OUTPUT VOLTAGE AT PCM ÐContinued
Page 3995 of 4284

Symptom:
P1391-INTERMITTENT LOSS OF CMP OR CKP
When Monitored and Set Condition:
P1391-INTERMITTENT LOSS OF CMP OR CKP
When Monitored: Engine running or cranking.
Set Condition: When the failure counter reaches 20 for 2 consecutive trips.
POSSIBLE CAUSES
WIRING HARNESS INSPECTION
TONE WHEEL/PULSE RING INSPECTION
WIRING HARNESS INSPECTION
TONE WHEEL/PULSE RING INSPECTION
CHECKING INTERMITTENT CKP SIGNAL WITH LAB
CHECKING INTERMITTENT CMP SIGNAL WITH LAB
CHECKING INTERMITTENT CKP WIRING WITH LAB SCOPE
CHECKING INTERMITTENT CMP WIRING WITH LAB SCOPE
INTERMITTENT CONDITION
CAMSHAFT POSITION SENSOR
CRANKSHAFT POSITION SENSOR
TEST ACTION APPLICABILITY
1 Turn the ignition on.
With the DRBIIIt, read DTC's.
Is the Good Trip displayed and equal to zero?All
Ye s®Go To 2
No®Go To 10
2 Turn the ignition off.
With the DRBIIItlab scope probe and the Miller special tool #6801, backprobe the
CMP Signal circuit in the CMP harness connector.
WARNING: KEEP CLEAR OF THE ENGINE'S MOVING PARTS.
Start the engine.
Observe the lab scope screen.
Are there any irregular or missing signals?All
Ye s®Go To 3
No®Go To 6
201
DRIVEABILITY - GAS
Page 3996 of 4284

TEST ACTION APPLICABILITY
3 Visually inspect the related wiring harness. Look for any chafed, pierced, pinched, or
partially broken wires.
Visually inspect the related wiring harness connectors. Look for broken, bent, pushed
out, or corroded terminals.
Ensure the Crankshaft Position Sensor and the Camshaft Position Sensor are
properly installed and the mounting bolt(s) tight.
Refer to any TSB that may apply.
Were any of the above conditions present?All
Ye s®Repair as necessary
Perform POWERTRAIN VERIFICATION TEST VER - 5.
No®Go To 4
4 Turn the ignition off.
Remove the Camshaft Position Sensor.
Inspect the Tone Wheel/Pulse Ring for damage, foreign material, or excessive
movement.
Were any problems found?All
Ye s®Repair or replace the Tone Wheel/Pulse Ring as necessary.
Perform POWERTRAIN VERIFICATION TEST VER - 5.
No®Go To 5
5 If there are no possible causes remaining, view repair. All
Repair
Replace the Camshaft Position Sensor.
Perform POWERTRAIN VERIFICATION TEST VER - 5.
6 Turn the ignition off.
With the DRBIIItlab scope probe and the Miller special tool #6801, backprobe the
CKP Signal circuit in the CKP harness connector.
WARNING: KEEP CLEAR OF THE ENGINE'S MOVING PARTS.
Start the engine.
Observe the lab scope screen.
Are there any irregular or missing signals?All
Ye s®Go To 7
No®Go To 10
7 Visually inspect the related wiring harness. Look for any chafed, pierced, pinched, or
partially broken wires.
Visually inspect the related wiring harness connectors. Look for broken, bent, pushed
out, or corroded terminals.
Ensure the Crankshaft Position Sensor and the Camshaft Position Sensor are
properly installed and the mounting bolt(s) tight.
Refer to any TSB that may apply.
Were any of the above conditions present?All
Ye s®Repair as necessary
Perform POWERTRAIN VERIFICATION TEST VER - 5.
No®Go To 8
202
DRIVEABILITY - GAS
P1391-INTERMITTENT LOSS OF CMP OR CKP ÐContinued
Page 3997 of 4284

TEST ACTION APPLICABILITY
8 Turn the ignition off.
Remove the Crankshaft Position Sensor.
Inspect the Tone Wheel/Flex Plate slots for damage, foreign material, or excessive
movement.
Were any problems found?All
Ye s®Repair or replace the Tone Wheel/Flex Plate as necessary.
Perform POWERTRAIN VERIFICATION TEST VER - 5.
No®Go To 9
9 If there are no possible causes remaining, view repair. All
Repair
Replace the Crankshaft Position Sensor.
Perform POWERTRAIN VERIFICATION TEST VER - 5.
10 Turn the ignition off.
With the DRBIIItlab scope probe and the Miller special tool #6801, backprobe the
CKP Signal circuit in the PCM harness connector.
WARNING: WHEN THE ENGINE IS OPERATING, DO NOT STAND IN A
DIRECT LINE WITH THE FAN. DO NOT PUT YOUR HANDS NEAR THE
PULLEYS, BELTS OR FAN. DO NOT WEAR LOOSE CLOTHING.
Turn the ignition on. (do not start the engine)
Observe the lab scope screen.
Look for any pulses generated by the CKP Sensor.
Did the CKP Sensor generate any pulses?All
Ye s®Replace the Crankshaft Position Sensor.
Perform POWERTRAIN VERIFICATION TEST VER - 5.
No®Go To 11
11 Turn the ignition off.
With the DRBIIItlab scope probe and the Miller special tool #6801, backprobe the
CMP Signal circuit in the PCM harness connector.
WARNING: WHEN THE ENGINE IS OPERATING, DO NOT STAND IN A
DIRECT LINE WITH THE FAN. DO NOT PUT YOUR HANDS NEAR THE
PULLEYS, BELTS OR FAN. DO NOT WEAR LOOSE CLOTHING.
Turn the ignition on. (do not start the engine)
Observe the lab scope screen.
Look for any pulses generated by the CMP Sensor.
Did the CMP Sensor generate any pulses?All
Ye s®Replace the Camshaft Position Sensor.
Perform POWERTRAIN VERIFICATION TEST VER - 5.
No®Go To 12
203
DRIVEABILITY - GAS
P1391-INTERMITTENT LOSS OF CMP OR CKP ÐContinued
Page 3998 of 4284

TEST ACTION APPLICABILITY
12 Turn the ignition off.
With the DRBIIItlab scope probe and the Miller special tool #6801, backprobe the
CKP Signal circuit in the PCM harness connector.
WARNING: WHEN THE ENGINE IS OPERATING, DO NOT STAND IN A
DIRECT LINE WITH THE FAN. DO NOT PUT YOUR HANDS NEAR THE
PULLEYS, BELTS OR FAN. DO NOT WEAR LOOSE CLOTHING.
Start the engine.
Observe the lab scope screen while wiggling the wiring harness and connectors.
Were there any irregularities in the lab scope pattern?All
Ye s®Check the harness connectors carefully. If OK, replace the Crank-
shaft Position Sensor.
Perform POWERTRAIN VERIFICATION TEST VER - 5.
No®Go To 13
13 Turn the ignition off.
With the DRBIIItlab scope probe and the Miller special tool #6801, backprobe the
CMP Signal circuit in the PCM harness connector.
WARNING: WHEN THE ENGINE IS OPERATING, DO NOT STAND IN A
DIRECT LINE WITH THE FAN. DO NOT PUT YOUR HANDS NEAR THE
PULLEYS, BELTS OR FAN. DO NOT WEAR LOOSE CLOTHING.
Start the engine.
Observe the lab scope screen while wiggling the wiring harness and connectors.
Were there any irregularities in the lab scope pattern?All
Ye s®Check the harness connectors carefully. If OK, replace the Cam-
shaft Position Sensor.
Perform POWERTRAIN VERIFICATION TEST VER - 5.
No®Go To 14
14WARNING: WHEN THE ENGINE IS OPERATING, DO NOT STAND IN A
DIRECT LINE WITH THE FAN. DO NOT PUT YOUR HANDS NEAR THE
PULLEYS, BELTS OR FAN. DO NOT WEAR LOOSE CLOTHING.
NOTE: The conditions that set the DTC are not present at this time. The
following list may help in identifying the intermittent condition.
With the engine running at normal operating temperature, monitor the DRB
parameters related to the DTC while wiggling the wiring harness. Look for param-
eter values to change and/or a DTC to set.
Review the DRB Freeze Frame information. If possible, try to duplicate the
conditions under which the DTC was set.
Refer to any Technical Service Bulletins (TSB) that may apply.
Visually inspect the related wiring harness. Look for any chafed, pierced, pinched, or
partially broken wires.
Visually inspect the related wiring harness connectors. Look for broken, bent, pushed
out, or corroded terminals.
Were any of the above conditions present?All
Ye s®Repair as necessary
Perform POWERTRAIN VERIFICATION TEST VER - 5.
No®Test Complete.
204
DRIVEABILITY - GAS
P1391-INTERMITTENT LOSS OF CMP OR CKP ÐContinued
Page 3999 of 4284

Symptom:
P1398-MIS-FIRE ADAPTIVE NUMERATOR AT LIMIT
When Monitored and Set Condition:
P1398-MIS-FIRE ADAPTIVE NUMERATOR AT LIMIT
When Monitored: Under closed throttle decel with A/C off, ECT above 75, and more than
50 seconds after engine start.
Set Condition: One of the CKP sensor target windows has more than 2.86% variance from
the reference window.
POSSIBLE CAUSES
INTERMITTENT CONDITION
TONE WHEEL/PULSE RING INSPECTION
WIRING HARNESS INSPECTION
CRANKSHAFT POSITION SENSOR
TEST ACTION APPLICABILITY
1Note: Check for any TSB's that may apply to this symptom.
Turn the ignition on.
With the DRBIIItin the miscellaneous menu, choose Clear PCM battery disconnect
to reset the PCM.
With the DRBIIIt, choose the Misfire Pretest
Road test the vehicle and relearn the adaptive numerator.
The adaptive numerator is learned when the Adaptive Numerator Done Learning
line on the Misfire screen changes to Yes.
Did the adaptive numerator relearn?All
Ye s®Go To 2
No®Go To 3
205
DRIVEABILITY - GAS
Page 4000 of 4284

TEST ACTION APPLICABILITY
2WARNING: WHEN THE ENGINE IS OPERATING, DO NOT STAND IN A
DIRECT LINE WITH THE FAN. DO NOT PUT YOUR HANDS NEAR THE
PULLEYS, BELTS OR FAN. DO NOT WEAR LOOSE CLOTHING.
NOTE: The conditions that set the DTC are not present at this time. The
following list may help in identifying the intermittent condition.
With the engine running at normal operating temperature, monitor the DRB
parameters related to the DTC while wiggling the wiring harness. Look for param-
eter values to change and/or a DTC to set.
Review the DRB Freeze Frame information. If possible, try to duplicate the
conditions under which the DTC was set.
Refer to any Technical Service Bulletins (TSB) that may apply.
Visually inspect the related wiring harness. Look for any chafed, pierced, pinched, or
partially broken wires.
Visually inspect the related wiring harness connectors. Look for broken, bent, pushed
out, or corroded terminals.
Were any of the above conditions present?All
Ye s®Repair as necessary
Perform POWERTRAIN VERIFICATION TEST VER - 5.
No®Test Complete.
3 Visually inspect the CKP wiring harness. Look for any chafed, pierced, pinched, or
partially broken wires.
Visually inspect the CKP wiring harness connectors. Look for broken, bent, pushed
out, or corroded terminals.
Ensure the Crankshaft Position Sensor properly installed and the mounting bolt(s)
tight.
Refer to any TSB that may apply.
Were any of the above conditions present?All
Ye s®Repair as necessary
Perform POWERTRAIN VERIFICATION TEST VER - 5.
No®Go To 4
4 Turn the ignition off.
Remove the Crankshaft Position Sensor.
Inspect the Tone Wheel/Flex Plate slots for damage, foreign material, or excessive
movement.
Were any problems found?All
Ye s®Repair or replace the Tone Wheel/Flex Plate as necessary.
Perform POWERTRAIN VERIFICATION TEST VER - 5.
No®Go To 5
5 If there are no possible causes remaining, view repair. All
Repair
Replace the Crankshaft Position Sensor.
Perform POWERTRAIN VERIFICATION TEST VER - 5.
206
DRIVEABILITY - GAS
P1398-MIS-FIRE ADAPTIVE NUMERATOR AT LIMIT ÐContinued