Diagnostic Test

CHECK FOR AN ACTIVE DTC
1. With the scan tool, read all 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. With the scan tool, read TCM DTCs.
  Did the DTC return?
  
  Yes
  - Go To 2
  No
  - Perform the TESTING FOR AN INTERMITTENT CONDITION procedure. Refer to TESTING FOR AN INTERMITTENT CONDITION .
CHECK THE (T376) 5-VOLT CIRCUIT FOR OPEN/HIGH RESISTANCE
1. Turn the ignition off.
2. Disconnect the TCM harness connector.
3. Disconnect the Transmission Assembly harness connector.
4. Measure the resistance of the (T376) 5-Volt Supply circuit between the TCM harness connector and the Transmission Assembly harness connector.
  Is the resistance below 3.0 Ohms?
  
  Yes
  - Go To 3
  No
  - Repair the (T376) 5-Volt Supply circuit for an open circuit or high resistance.
  - Perform the TRANSMISSION VERIFICATION TEST. Refer to TRANSMISSION VERIFICATION TEST - 948TE 9HP48 .
CHECK THE (T377) OIL PRESSURE SIGNAL CIRCUIT FOR OPEN/HIGH RESISTANCE
1. Measure the resistance of (T377) Oil Pressure Signal circuit between the TCM harness connector and the Transmission Assembly harness connector.
  Is the resistance below 3.0 Ohms?
  
  Yes
  
  Go To 4
  
  No
  - Repair the (T377) Oil Pressure Signal circuit for an open or high resistance.
  - Perform the TRANSMISSION VERIFICATION TEST. Refer to TRANSMISSION VERIFICATION TEST - 948TE 9HP48 .
CHECK (T377) OIL PRESSURE SIGNAL CIRCUIT FOR A SHORT TO GROUND OR ANOTHER CIRCUIT
1. Check for continuity between ground and the (T377) Oil Pressure Signal circuit at the TCM harness connector.
2. Check for continuity between the (T377) Oil Pressure Signal circuit and all other circuits at the TCM harness connector.
  Is there continuity between the (T377) Oil Pressure Signal circuit and ground or any other circuit?
  
  Yes
  - Repair the (T377) Oil Pressure Signal circuit for a short to ground or another circuit.
  - Perform the TRANSMISSION VERIFICATION TEST. Refer to TRANSMISSION VERIFICATION TEST - 948TE 9HP48 .
  No
  
  Go To 5
CHECK INTERNAL HARNESS AND CONNECTIONS
1. Remove the Transmission Oil Pan.
2. Check the Transmission internal wiring harness and Transmission Fluid Pressure Sensor electrical connections for open circuits, shorts, and loose connections.
  Were any problems found?
  
  Yes
  - Repair the condition as necessary.
  - Perform the TRANSMISSION VERIFICATION TEST. Refer to TRANSMISSION VERIFICATION TEST - 948TE 9HP48 .
  No
  
  Go To 6
REPLACE THE OIL PRESSURE SENSOR AND RETEST FOR DTC
NOTE:
Check for part availability, the Transmission Fluid Pressure Sensor may only be available with the Valve Body assembly.
1. Replace the Transmission Fluid Pressure Sensor in accordance with the Service Information. Refer to SENSOR, FLUID PRESSURE, REMOVAL .
2. Turn the ignition on.
3. With the scan tool, erase all DTCs.
4. Turn the ignition off for a minimum of 10.0 seconds.
5. Turn the ignition on.
6. Using the When Monitored and Set Conditions above and recorded data, operate the vehicle in the conditions that set the DTC.
7. With the scan tool, read DTCs.
  Did the DTC return?
  
  Yes
  
  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 (TCM), REMOVAL .
  - Perform the TRANSMISSION VERIFICATION TEST. Refer to TRANSMISSION VERIFICATION TEST - 948TE 9HP48 .
  No
  - Test Complete.