Diagnostic Test
- DETERMINE IF RELATED TCM POWER INPUT DTCS ARE PRESENT
- Using the scan tool, check for transmission DTCs.
Are there any TCM Power Control circuit or TCM Power Input DTCs present?
Yes
- Perform the appropriate diagnostic procedure.
- Perform 68RFE TRANSMISSION VERIFICATION TEST. Refer to STANDARD PROCEDURE .
No
- Go To 2
- Using the scan tool, check for transmission DTCs.
- CHECK IF THE DTC DATA SHOWS THE CURRENT DTC
- With the scan tool, read and record the Event Data.NOTE:
Make sure to record all Event Data stored in the scan tool for future reference in this test procedure.
Does the Event Data show data for DTC P0846?
Yes
- Go To 3
No
- Refer to DIAGNOSIS AND TESTING and perform the appropriate diagnostic procedure shown in the Event Data.
- Perform 68RFE TRANSMISSION VERIFICATION TEST. Refer to STANDARD PROCEDURE .
- With the scan tool, read and record the Event Data.
- CHECK IF MULTIPLE DTCS ARE PRESENT
- CHECK IF ALL THE PRESSURE SWITCHES READ CLOSED
- With the scan tool, check the Event Data for P0846.NOTE:
Make sure to record all Event Data stored in the scan tool for future reference in this test procedure.
Do all the pressure switches read CLOSED in the Event Data for P0846?
Yes
- Refer to DIAGNOSIS AND TESTING and perform diagnostics for P0882.
No
- Go To 5
- With the scan tool, check the Event Data for P0846.
- CHECK IF ALL THE PRESSURE SWITCHES READ OPEN
In the Event Data recorded earlier, do all the pressure switches read OPEN?
Yes
- Go To 6
No
- Go To 7
- CHECK FOR LOW LINE PRESSURE
In the Event Data recorded earlier, is the (actual) Line Pressure less than 276 kPa (40 psi), and significantly below the Desired (target) Line Pressure?
Yes
- Repair as necessary to correct low line pressure. Check fluid level and adjust as necessary. If fluid level is OK, check the Primary Oil Filter seal for a split, crack, or improperly installed. If the filter and seal are OK, check the Main Regulator Valve in the Oil Pump. Refer to the Service Information for the above procedures.
- Perform the 68RFE TRANSMISSION VERIFICATION TEST. Refer to STANDARD PROCEDURE .
No
- Replace the Transmission Solenoid/TRS Assembly in accordance with the Service Information.
- Perform the 68RFE TRANSMISSION VERIFICATION TEST. Refer to STANDARD PROCEDURE .
- CHECK IF THE DTC SET IN PARK, NEUTRAL, OR REVERSE
- CHECK IF THE 2C PRESSURE SWITCH READS CLOSED
In the Event Data recorded earlier, does the Event Data show the 2C Pressure Switch reading CLOSED?
Yes
- Go To 10
No
- Go To 9
- CHECK THE LINE PRESSURE
In the Event Data recorded earlier, is the (actual) Line Pressure less than 276 kPa (40 psi), and significantly below the Desired (target) Line Pressure?
Yes
- Repair as necessary to correct low line pressure. Check fluid level and adjust as necessary. If fluid level is OK, check the Primary Oil Filter seal for a split, crack, or improperly installed. If the filter and seal are OK, check the Main Regulator Valve in the Oil Pump. Refer to the Service Information for the above procedures.
- Perform the 68RFE TRANSMISSION VERIFICATION TEST. Refer to STANDARD PROCEDURE .
No
- Go To 15
- CHECK THE PCM AND WIRING USING THE TRANSMISSION SIMULATOR
- Turn the ignition off.
- Remove the Starter Relay from the PDC.CAUTION:
Removal of the Starter Relay will prevent the vehicle from being started in gear.
WARNING:The Starter Relay must be removed from the PDC. Failure to do so may result in possible serious or fatal injury.
- Install the Transmission Simulator (special tool #8333B, Simulator, Transmission).
- Ignition on, engine not running.
- With the Transmission Simulator, turn the Pressure Switch selector switch to the 2C position.
- With the scan tool, monitor the 2C Pressure Switch while pressing the Pressure Switch test button on the Transmission Simulator.
Did the state of the 2C Pressure Switch change while pressing the Pressure Switch Test button?
Yes
- Go To 11
No
- Go To 12
- CHECK THE TRANSMISSION SOLENOID/TRS ASSEMBLY
- Using the schematics as a guide, inspect the wiring and connectors specific to this circuit.
- Wiggle the wires while checking for shorted and open circuits.
Where there any problems found?
Yes
- Repair as necessary.
- Perform the 68RFE TRANSMISSION VERIFICATION TEST. Refer to STANDARD PROCEDURE .
No
- Replace the Transmission Solenoid/TRS Assembly in accordance with the Service Information.
- Perform the 68RFE TRANSMISSION VERIFICATION TEST. Refer to STANDARD PROCEDURE .
- CHECK THE (T147) 2C PRESSURE SWITCH SENSE CIRCUIT FOR AN OPEN
- Turn the ignition off.
- Disconnect the Transmission Simulator (special tool #8333B, Simulator, Transmission).
- Disconnect the PCM C2 harness connector.
- Measure the resistance of the (T147) 2C Pressure Switch Sense circuit between the Transmission Solenoid/TRS Assembly harness connect and the appropriate terminal of the PCM C2 harness connector.
Is the resistance above 5.0 Ohms?
Yes
- Repair the (T147) 2C Pressure Switch Sense circuit for an open.
- Perform the 68RFE TRANSMISSION VERIFICATION TEST. Refer to STANDARD PROCEDURE .
No
- Go To 13
- CHECK THE (T147) 2C PRESSURE SWITCH SENSE CIRCUIT FOR A SHORT TO GROUND
- Measure the resistance between ground and the (T147) 2C Pressure Switch Sense circuit.
Is the resistance below 5.0 Ohms?
Yes
- Repair the (T147) 2C Pressure Switch Sense circuit for a short to ground.
- Perform the 68RFE TRANSMISSION VERIFICATION TEST. Refer to STANDARD PROCEDURE .
No
- Go To 14
- Measure the resistance between ground and the (T147) 2C Pressure Switch Sense circuit.
- CHECK THE (T147) 2C PRESSURE SWITCH SENSE CIRCUIT FOR A SHORT TO ANOTHER CIRCUIT
- Measure the resistance between the (T147) 2C Pressure Switch Sense circuit and all the other circuits in the Transmission Solenoid/TRS Assembly harness connector.
Is the resistance below 5.0 Ohms?
Yes
- Repair the (T147) 2C Pressure Switch Sense circuit for a short to another circuit(s).
- Perform the 68RFE TRANSMISSION VERIFICATION TEST. Refer to STANDARD PROCEDURE .
No
- Using the schematics as a guide, check the Powertrain Control Module (PCM) terminals for corrosion, damage, or terminal push out. Pay particular attention to all power and ground circuits. If no problems are found, replace the PCM in accordance with the Service Information. With the scan tool, perform Quick Learn.
- Perform the 68RFE TRANSMISSION VERIFICATION TEST. Refer to STANDARD PROCEDURE .
- Measure the resistance between the (T147) 2C Pressure Switch Sense circuit and all the other circuits in the Transmission Solenoid/TRS Assembly harness connector.
- CHECK IF THE NO. 5 CHECK BALL IS CUT OR DAMAGED
- Turn the Ignition off.
- Remove the Valve Body Assembly in accordance with the Service Information.
- Inspect the No. 5 check ball for any cuts or damage.
- Inspect the 2C accumulator piston and seals and also the 2C tower seal on top of the valve body. Refer to the Service Information.
Where there any problems found?
Yes
- Repair as necessary. Check for excessive clutch debris in the transmission oil pan. If excessive clutch debris is present, repair 2C clutch as necessary. Refer to the Service Information for proper repair procedures.
- Perform the 68RFE TRANSMISSION VERIFICATION TEST. Refer to STANDARD PROCEDURE .
No
- Go To 16
- CHECK FOR EXCESSIVE FLUID LEAKAGE WITHIN THE 2C CLUTCH CIRCUIT
- Air check the 2C Clutch hydraulic circuit. Refer to the Service Information.NOTE:
This hydraulic clutch circuit contains a small bleed orifice. Small leakage is considered normal.
Was there excessive air leakage in the 2C Clutch hydraulic circuit?
Yes
- Repair as necessary. Refer to the Service Information.
- Perform the 68RFE TRANSMISSION VERIFICATION TEST. Refer to STANDARD PROCEDURE .
No
- Replace the Transmission Solenoid/TRS Assembly in accordance with the Service Information.
- Perform the 68RFE TRANSMISSION VERIFICATION TEST. Refer to STANDARD PROCEDURE .
- Air check the 2C Clutch hydraulic circuit. Refer to the Service Information.