Diagnostic Test

CHECK FOR AN ACTIVE DTC
1. With the scan tool, read TCM DTCs and record on the repair order.
2. Record the Event Data and Environmental Data.
3. With the scan tool, erase DTCs.
4. Using the recorded Event and Environmental Data, along with the When Monitored and Set Conditions above, operate the vehicle in the conditions that set the DTC.
5. Read TCM DTCs.
  Did the DTC return?
  
  Yes
  - Go To 2
  No
  - Go To 9
CHECK THE PRESSURE CONTROL SOLENOID - LINE PRESSURE
1. Turn the ignition off.
2. Disconnect the Transmission Assembly harness connector.
3. Measure the resistance of the Pressure Control Solenoid Line Pressure at the appropriate terminals in the Transmission Assembly interface connector.
  Is the resistance of the Pressure Control Solenoid Line Pressure between 10.0 and 12.0 Ohms?
  
  Yes
  - Go To 3
  No
  - Replace the Pressure Control Solenoid Line Pressure in accordance with the Service Information.
  - Perform the TRANSMISSION VERIFICATION TEST. Refer to TRANSMISSION VERIFICATION TEST - 948RE 9HP48 .
CHECK THE (T78) SOLENOID SUPPLY 1 CIRCUIT FOR AN OPEN
1. Disconnect the TCM harness connector.
2. Measure the resistance of the (T78) Solenoid Supply 1 circuit between the Transmission Assembly harness connector and the TCM harness connector.
  Is the resistance below 3.0 Ohms?
  
  Yes
  - Go To 4
  No
  - Repair the (T78) Solenoid Supply 1 circuit for an open or high resistance.
  - Perform the TRANSMISSION VERIFICATION TEST. Refer to TRANSMISSION VERIFICATION TEST - 948RE 9HP48 .
CHECK THE (T78) SOLENOID SUPPLY 1 CIRCUIT FOR A SHORT TO GROUND
1. Measure the resistance between ground and the (T78) Solenoid Supply 1 circuit.
  Is there continuity between ground and the (T78) Solenoid Supply 1 circuit?
  
  Yes
  - Repair the (T78) Solenoid Supply 1 circuit for a short to ground.
  - Perform the TRANSMISSION VERIFICATION TEST. Refer to TRANSMISSION VERIFICATION TEST - 948RE 9HP48 .
  No
  - Go To 5
CHECK THE (T78) SOLENOID SUPPLY 1 CIRCUIT FOR A SHORT TO ANOTHER CIRCUIT
1. Measure the resistance between the (T78) Solenoid Supply 1 circuit and all other circuits in the TCM harness connector.
  Is there continuity between the (T78) Solenoid Supply 1 circuit and any other circuits in the TCM harness connector?
  
  Yes
  - Repair the (T78) Solenoid Supply 1 circuit for a short to another circuit.
  - Perform the TRANSMISSION VERIFICATION TEST. Refer to TRANSMISSION VERIFICATION TEST - 948RE 9HP48 .
  No
  - Go To 6.
CHECK THE (T812) PRESSURE CONTROL SOLENOID LINE PRESSURE CIRCUIT FOR AN OPEN
1. Measure the resistance of the (T812) Pressure Control Solenoid Line Pressure circuit between the Transmission Assembly harness connector and the TCM harness connector.
  Is the resistance below 3.0 Ohms?
  
  Yes
  - Go To 7
  No
  - Repair the (T812) Pressure Control Solenoid Line Pressure circuit for an open or high resistance.
  - Perform the TRANSMISSION VERIFICATION TEST. Refer to TRANSMISSION VERIFICATION TEST - 948RE 9HP48 .
CHECK THE (T812) PRESSURE CONTROL SOLENOID LINE PRESSURE CIRCUIT FOR A SHORT TO GROUND
1. Measure the resistance between ground and the (T812) Pressure Control Solenoid Line Pressure circuit.
  Is there continuity between ground and the (T812) Pressure Control Solenoid Line Pressure circuit?
  
  Yes
  - Repair the (T812) Pressure Control Solenoid Line Pressure circuit for a short to ground.
  - Perform the TRANSMISSION VERIFICATION TEST. Refer to TRANSMISSION VERIFICATION TEST - 948RE 9HP48 .
  No
  - Go To 8.
CHECK THE (T812) PRESSURE CONTROL SOLENOID LINE PRESSURE CIRCUIT FOR A SHORT TO ANOTHER CIRCUIT
1. Measure the resistance between the (T812) Pressure Control Solenoid Line Pressure circuit and all other circuits in the TCM harness connector.
  Is there continuity between the (T812) Pressure Control Solenoid Line Pressure circuit and any other circuits in the TCM harness connector?
  
  Yes
  - Repair the (T812) Pressure Control Solenoid Line Pressure circuit for a short to another circuit.
  - Perform the TRANSMISSION VERIFICATION TEST. Refer to TRANSMISSION VERIFICATION TEST - 948RE 9HP48 .
  No
  
  NOTE:
  If this Electronic Control Unit (ECU) is being replaced with a new unit, a diagnostic scan tool MUST be used to align the PROXI configuration data into the new ECU. Follow the routine outlined in the diagnostic scan tool for PROXI Configuration Alignment under Body Control Module (BCM) Miscellaneous Functions menu.
  - Using the schematics as a guide, check the Transmission Control Module (TCM) terminals and connectors for corrosion, damage or pushed out terminals. Pay particular attention to the power and ground circuits. If no problems are found, replace the TCM and perform programming and PROXI Configuration Alignment procedures. Refer to MODULE, TRANSMISSION CONTROL, REMOVAL .
  - Perform the TRANSMISSION VERIFICATION TEST. Refer to TRANSMISSION VERIFICATION TEST - 948RE 9HP48 .
CHECK THE WIRING AND CONNECTORS
1. The conditions necessary to set this DTC are not present at this time.
2. Use the Event Data to help duplicate the conditions in which the DTC originally set. Pay particular attention to the DTC set conditions, such as, VSS, MAP, ECT, and Load.
3. Using the schematics as a guide, visually inspect the related wiring harness. Look for any chafed, pierced, pinched, or partially broken wires.
4. Visually inspect the related wiring harness connectors. Look for broken, bent, pushed out, or corroded terminals.
5. Wiggle the wires while checking for shorted and open circuits.
6. Check for any Service Bulletins that may apply.
  Were any problems found?
  
  Yes
  - Repair as necessary.
  - Perform the TRANSMISSION VERIFICATION TEST. Refer to TRANSMISSION VERIFICATION TEST - 948RE 9HP48 .
  No
  - Test complete.