Page 4249 of 4284

TEST ACTION APPLICABILITY
10 Turn the ignition off to the lock position.
Disconnect the TCM harness connector.
Disconnect the TRS harness connector.
Note: Check connectors - Clean/repair as necessary.
Measure the resistance between ground and the Transmission Temperature Sensor
Signal circuit.
Is the resistance below 5.0 ohms?All
Ye s®Repair Transmission Temperature Sensor Signal circuit shorted
to ground.
Perform 41TE TRANSMISSION VERIFICATION TEST - VER 1.
No®Go To 11
11 If there are no possible causes remaining, view repair. All
Repair
Replace the TCM. WITH THE DRBIIItPERFORM QUICK
LEARN AND REPROGRAM PINION FACTOR.
Perform 41TE TRANSMISSION VERIFICATION TEST - VER 1.
12 The conditions necessary to set this DTC are not present at this time.
Using the schematics as a guide, inspect the wiring and connectors specific to this
circuit.
Wiggle the wiring while checking for shorts and open circuits.
Were there any problems found?All
Ye s®Repair as necessary.
Perform 41TE TRANSMISSION VERIFICATION TEST - VER 1.
No®Test Complete.
145
TRANSMISSION
P1799-CALCULATED OIL TEMP IN USE ÐContinued
Page 4250 of 4284

Symptom:
*BRAKE SHIFT INTERLOCK OUTPUT OPEN
POSSIBLE CAUSES
INTERMITTENT WIRING AND CONNECTORS
BRAKE SHIFT INTERLOCK CONTROL CIRCUIT OPEN
BRAKE SHIFT INTERLOCK FEED CIRCUIT OPEN
BRAKE SHIFT INTERLOCK SOLENOID
FRONT CONTROL MODULE
TEST ACTION APPLICABILITY
1 Ignition on, engine not running.
With the DRBIIIt, record and erase DTC's.
Turn the ignition off to the lock position.
Turn the ignition on.
With the DRBIIIt, read DTCs.
Does the DRBIIItdisplay BRAKE SHIFT INTERLOCK OUTPUT OPEN?All
Ye s®Go To 2
No®Go To 8
2 Turn the ignition off to the lock position.
Disconnect the Brake Shift Interlock harness connector.
Note: Check connectors - Clean/repair as necessary.
Ignition on, engine not running.
Using a 12-volt test light connected to B+, check the Brake Shift Interlock Control
circuit in the Brake Shift Interlock harness connector.
NOTE: The test light must illuminate brightly. Compare the brightness to
that of a direct connection to the battery.
Does the test light illuminate brightly?All
Ye s®Go To 3
No®Go To 6
3 Turn the ignition off to the lock position.
Disconnect the Brake Shift Interlock harness connector.
Note: Check connectors - Clean/repair as necessary.
Ignition on, engine not running.
Using a 12-volt test light connected to ground, check the Brake Shift Interlock Feed
circuit in the Brake Shift Interlock harness connector.
NOTE: The test light must illuminate brightly. Compare the brightness to
that of a direct connection to the battery.
Does the test light illuminate brightly?All
Ye s®Go To 4
No®Go To 5
4 If there are no possible causes remaining, view repair. All
Repair
Replace the Brake Shift Interlock Solenoid in accordance with the
Service Information.
146
TRANSMISSION
Page 4251 of 4284

TEST ACTION APPLICABILITY
5 Turn the ignition off to the lock position.
Disconnect the Front Control Module harness connector.
Disconnect the Brake Shift Interlock harness connector.
Note: Check connectors - Clean/repair as necessary.
Measure the resistance of the Brake Shift Interlock Feed Circuit from the Front
Control Module connector to the Brake Shift Interlock harness connector.
Is the resistance above 5.0 ohms?All
Ye s®Repair the Brake Shift Interlock Feed Circuit for an open.
No®Go To 7
6 Turn the ignition off to the lock position.
Disconnect the Front Control Module harness connector.
Disconnect the Brake Shift Interlock harness connector.
Note: Check connectors - Clean/repair as necessary.
Measure the resistance of the Brake Shift Interlock Control Circuit from the Front
Control Module connector to the Brake Shift Interlock harness connector.
Is the resistance above 5.0 ohms?All
Ye s®Repair the Brake Shift Interlock Control Circuit for an open.
No®Go To 7
7 If there are no possible causes remaining, view repair. All
Repair
Replace the Front Control Module in accordance with the Service
Information.
8 The conditions necessary to set this DTC are not present at this time.
Using the schematics as a guide, inspect the wiring and connectors specific to this
circuit.
Wiggle the wiring while checking for shorts and open circuits.
Were there any problems found?All
Ye s®Repair as necessary.
No®Test Complete.
147
TRANSMISSION
*BRAKE SHIFT INTERLOCK OUTPUT OPEN ÐContinued
Page 4252 of 4284

Symptom:
*CHECKING PARK/NEUTRAL SWITCH OPERATION
POSSIBLE CAUSES
P/N POSITION SWITCH SENSE CIRCUIT OPEN
P/N POSITION SWITCH SENSE CIRCUIT SHORTED TO GROUND
TRANSMISSION RANGE SENSOR
PCM - P/N POSITION SWITCH
TEST ACTION APPLICABILITY
1 Turn the ignition on.
With the DRBIIIt, read the Park/Neutral Position Switch input state.
While moving the gear selector through all gear positions, Park to 1 and back to Park,
watch the DRBIIItdisplay.
Did the DRBIIItdisplay show P/N and D/R in the correct gear positions?All
Ye s®Test Complete.
No®Go To 2
2 Turn the ignition off.
Disconnect the PCM harness connectors.
Disconnect the Transmission Range Sensor harness connector.
Note: Check connectors - Clean/repair as necessary.
Measure the resistance of the P/N Position Switch Sense circuit.
Is the resistance below 5.0 ohms?All
Ye s®Go To 3
No®Repair the P/N Position Switch Sense circuit for an open.
3 Turn the ignition off.
Disconnect the PCM harness connectors.
Disconnect the Transmission Range Sensor harness connector.
Note: Check connectors - Clean/repair as necessary.
Measure the resistance between ground and the P/N Position Switch Sense circuit.
Is the resistance above 100k ohms?All
Ye s®Go To 4
No®Repair the P/N Position Switch Sense circuit for a short to ground.
4 Turn the ignition off.
Disconnect the PCM harness connectors.
Move the Gear selector through all gear positions, from Park to 1st and back.
While moving the gear selector through each gear, measure the resistance between
ground and the P/N Position Switch Sense circuit.
Did the resistance change from above 10.0 ohms to below 10.0 ohms?All
Ye s®Go To 5
No®Replace the Transmission Range Sensor.
148
TRANSMISSION
Page 4253 of 4284
TEST ACTION APPLICABILITY
5 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 - 2.
149
TRANSMISSION
*CHECKING PARK/NEUTRAL SWITCH OPERATION ÐContinued
Page 4254 of 4284
Symptom:
*INCORRECT TRANSMISSION FLUID LEVEL
POSSIBLE CAUSES
INCORRECT FLUID LEVEL
TEST ACTION APPLICABILITY
1 The transmission must be above 70 degree F. prior to checking fluid level. Adjusting
fluid level on a cold transmission will result in an overfilled transmission.
Check the transmission fluid level per the service information.
Is the fluid level OK?All
Ye s®Test Complete.
No®Adjust fluid level. Repair cause of incorrect fluid level.
150
TRANSMISSION
Page 4255 of 4284

Symptom:
*NO BACK UP LAMP OPERATION
POSSIBLE CAUSES
BCM - BACK UP LAMP DRIVER OPEN DTC PRESENT
BCM - BACK UP LAMP DRIVER SHORTED DTC PRESENT
BCM - BUS PROBLEM
IPM - BUS PROBLEM
LEFT REVERSE LAMP GROUND CIRCUIT OPEN
LEFT REVERSE LAMP OPEN
RIGHT REVERSE LAMP GROUND CIRCUIT OPEN
RIGHT REVERSE LAMP OPEN
TRS GROUND CIRCUIT OPEN
TRS REVERSE SENSE CIRCUIT OPEN TO IPM
TEST ACTION APPLICABILITY
1 With the DRBIIIt, read the BCM DTCs.
Is the Back Up Lamp Driver Open DTC Present?All
Ye s®Refer to the Body category and perform the appropriate symptom
diagnosis.
No®Go To 2
2 With the DRBIIIt, read the BCM DTCs.
Is the Back Up Lamp Driver Shorted DTC Present?All
Ye s®Refer to the Body category and perform the appropriate symptom
diagnosis.
No®Go To 3
3 With the DRBIIIt, attempt to communicate with the BCM.
Can the DRBIIItcommunicate with the BCM?All
Ye s®Go To 4
No®Refer to the Communication category and perform the appropri-
ate symptom diagnosis.
4 With the DRBIIIt, attempt to communicate with the IPM.
Can the DRBIIItcommunicate with the IPM?All
Ye s®Go To 5
No®Refer to the Communication category and perform the appropri-
ate symptom diagnosis.
151
TRANSMISSION
Page 4256 of 4284

TEST ACTION APPLICABILITY
5 Turn the ignition off to the lock position.
Disconnect the Left Reverse Lamp harness connector per the service information.
NOTE: Check connectors - Clean/repair as necessary.
Measure the resistance between ground and the Reverse Lamp Ground circuit.
Is the resistance below 5.0 ohms?All
Ye s®Go To 6
No®Repair the Reverse Lamp Ground circuit for an open.
6 Turn the ignition off to the lock position.
Disconnect the Left Reverse Lamp harness connector per the service information.
NOTE: Check connectors - Clean/repair as necessary.
Measure the resistance across the Reverse Lamp contacts.
Is the resistance above 5.0 ohms?All
Ye s®Replace the Reverse Lamp.
No®Go To 7
7 Turn the ignition off to the lock position.
Disconnect the Right Reverse Lamp harness connector per the service information.
NOTE: Check connectors - Clean/repair as necessary.
Measure the resistance between ground and the Reverse Lamp Ground circuit.
Is the resistance below 5.0 ohms?All
Ye s®Go To 8
No®Repair the Reverse Lamp Ground circuit for an open.
8 Turn the ignition off to the lock position.
Disconnect the Right Reverse Lamp harness connector per the service information.
NOTE: Check connectors - Clean/repair as necessary.
Measure the resistance across the Reverse Lamp contacts.
Is the resistance above 5.0 ohms?All
Ye s®Replace the Reverse Lamp.
No®Go To 9
9 Turn the ignition off to the lock position.
Disconnect the TRS harness connector.
NOTE: Check connectors - Clean/repair as necessary.
Measure the resistance between ground and the TRS Ground circuit.
Is the resistance below 5.0 ohms?All
Ye s®Go To 10
No®Repair the TRS Ground circuit for an open.
10 Turn the ignition off to the lock position.
Disconnect the IPM harness connector.
Disconnect the TRS harness connector.
NOTE: Check connectors - Clean/repair as necessary.
Measure the resistance of the TRS Reverse Sense circuit between the IPM connector
and the TRS connector.
Is the resistance below 5.0 ohms?All
Ye s®Test Complete.
No®Repair the TRS Reverse Sense circuit for an open.
152
TRANSMISSION
*NO BACK UP LAMP OPERATION ÐContinued