Diagnostic Test

1. With the scan tool, read TCM DTCs and record on the repair order.

   Is DTC P0933 set?

   Yes 

   • Repair DTC P0933. Refer to DIAGNOSTIC CODE INDEX .

   No 

   • Go To  2

1. With the scan tool, read DTCs in all Electronic Control Units (ECUs) and record on the repair order.
2. With the scan tool, run a vehicle Scan Report, or record the Environmental Data related to the DTCs.
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 recorded Environmental Data and the When Monitored Conditions above, operate the vehicle in the conditions that set the DTC.
7. With the scan tool, read DTCs.

Did the DTC return?

Yes 

• Go To  3

No 

• Go To  15

1. Turn the ignition on, Engine Off  .
2. With the scan tool, read the Line Pressure while firmly pushing the Line Pressure Sensor connector inwards towards the Transmission.

   Did the Line Pressure reading on the scan tool CHANGE to about 207 kPa (30 psi) or 0.7 volts when the connector was pushed inward?

   Yes (value was different and changed to 207 kPa (30 psi) or 0.7 volts). 

   • Disconnect and properly reconnect the Line Pressure Sensor connector. Inspect terminals and repair as necessary.
   • Perform the TRANSMISSION VERIFICATION TEST. Refer to TRANSMISSION VERIFICATION TEST .

   No 

   • Go To  4

1. Turn the ignition off.
2. Install the Line Pressure Adaptor (special tool #8259, Adapter, Pressure Test), and the 0-300 psi Pressure Gauge (special tool #C-3293-SP, Gauge, Pressure 0-300 P.S.I.).
3. Start the engine in PARK.
4. Monitor the line pressure readings of both the scan tool and the pressure gauge and compare the two readings.

   Is the line pressure gauge reading within 34 kPa (5 psi) of the scan tool reading?

   Yes 

   • Go To  13

   No 

   • Go To  5

1. Turn the ignition off.
2. Disconnect the Line Pressure Sensor harness connector.
3. Turn the ignition on.
   • Measure the voltage on the (F856) 5-Volt Supply circuit in the Line Pressure Sensor harness connector.

   Is the voltage above 4.8 volts?

   Yes 

   • Go To  9

   No 

   • Go To  6

1. Measure the resistance between the (F856) Line Pressure Sensor 5-Volt Supply circuit and the (K400) Sensor Ground circuit at the Transmission Line Pressure Sensor harness connector.

   Is the resistance above 10k Ohms?

   Yes 

   • Go To  7

   No 

   • Repair the (F856) 5-Volt Supply circuit for a short to the (K900) Sensor Ground circuit.
   • Perform the TRANSMISSION VERIFICATION TEST. Refer to TRANSMISSION VERIFICATION TEST .

1. Connect the (special tool #10436, Adapter, GPEC Diagnostic) to the PCM harness connector.
   1. The ignition must be off when checking a circuit for continuity to ground.
   2. Isolate the circuit by disconnecting the Electronic Control Unit (ECU) and every component harness connector containing the circuit being tested. Note:  Use the wiring diagram as a guide to follow the path of the circuit.
   3. Connect the negative lead of the DVOM to a known good ground.
   4. With the positive lead of the DVOM, probe the circuit being tested at the component harness connector and check for continuity between the circuit and ground.
   NOTE:

   There should be no continuity between ground and the circuit being tested.

   Is there continuity between ground and the circuit being tested?

   Yes 

   • Repair the circuit for a short to ground. Use the wiring diagram as a guide to trace the circuit and look for any in-line connectors to help isolate the location of the short.
   • Perform the TRANSMISSION VERIFICATION TEST. Refer to TRANSMISSION VERIFICATION TEST .

   No 

   • Go To  8

1. The ignition must be off when checking the continuity of a circuit.
2. Isolate the circuit by disconnecting the Electronic Control Unit (ECU) and the component harness connector containing the circuit being tested. Note:  Use the wiring diagram as a guide to follow the path of the circuit.
3. Before measuring the resistance of any circuit, first measure the resistance between the two leads of the DVOM. Note:  The meter leads can add resistance to the measurement value.
4. Connect one lead of the DVOM to the circuit being tested at the component harness connector.
5. Connect the other lead to the circuit being tested at the GPEC Diagnostic Adapter and measure the resistance of the circuit.

Is the resistance below 3.0 Ohms?

Yes 

• Go To  9

No 

• Repair the circuit for an open or high resistance.
• Perform the TRANSMISSION VERIFICATION TEST. Refer to TRANSMISSION VERIFICATION TEST .

1. The ignition must be off when checking a circuit for continuity to ground.
2. Isolate the circuit by disconnecting the Electronic Control Unit (ECU) and every component harness connector containing the circuit being tested. Note:  Use the wiring diagram as a guide to follow the path of the circuit.
3. Connect the negative lead of the DVOM to a known good ground.
4. With the positive lead of the DVOM, probe the circuit being tested at the component harness connector and check for continuity between the circuit and ground.

Is there continuity between ground and the circuit being tested?

Yes 

• Repair the circuit for a short to ground. Use the wiring diagram as a guide to trace the circuit and look for any in-line connectors to help isolate the location of the short.
• Perform the TRANSMISSION VERIFICATION TEST. Refer to TRANSMISSION VERIFICATION TEST .

No 

• Go To  10

1. Measure the resistance between the (T38) Line Pressure Signal circuit and the (K400) Sensor Ground circuit at the Line Pressure Sensor harness connector.

   Is the resistance above 10k Ohms?

   Yes 

   • Go To  11

   No 

   • Repair the (T38) Line Pressure Signal circuit for a short to the (K400) Sensor Ground circuit.
   • Perform the TRANSMISSION VERIFICATION TEST. Refer to TRANSMISSION VERIFICATION TEST .

1. The ignition must be off when checking the continuity of a circuit.
2. Isolate the circuit by disconnecting the Electronic Control Unit (ECU) and the component harness connector containing the circuit being tested. Note:  Use the wiring diagram as a guide to follow the path of the circuit.
3. Before measuring the resistance of any circuit, first measure the resistance between the two leads of the DVOM. Note:  The meter leads can add resistance to the measurement value.
4. Connect one lead of the DVOM to the circuit being tested at the component harness connector.
5. Connect the other lead to the circuit being tested at the GPEC Diagnostic Adapter and measure the resistance of the circuit.

Is the resistance below 3.0 Ohms?

Yes 

• Go To  12

No 

• Repair the circuit for an open or high resistance.
• Perform the TRANSMISSION VERIFICATION TEST. Refer to TRANSMISSION VERIFICATION TEST .

1. Turn the ignition off.
2. Disconnect the Line Pressure Sensor.
3. Connect a jumper wire between the (F856) 5-Volt supply and the (T38) line pressure signal circuits at the Line Pressure Sensor harness connector.
4. Turn the ignition on.
5. With the scan tool, read the Line Pressure Sensor signal voltage.

   Is the voltage above 4.8 volts with the jumper in place?

   Yes 

   • Replace the Line Pressure Sensor in accordance with the Service Information. Refer to SENSOR, VARIABLE LINE PRESSURE, REMOVAL AND INSTALLATION .
   • Perform the TRANSMISSION VERIFICATION TEST. Refer to TRANSMISSION VERIFICATION TEST .

   No 

   NOTE:

   This transmission is equipped with a solenoid for the Torque Converter Clutch (TCC) that is a Variable Force Solenoid (VFS) with close tolerance Pressure/Inductance (PI) curve. If replacing the PCM, it is necessary to transfer the PI data from the old PCM to the new PCM using the scan tool. If the PCM being replaced is non-responsive, the PI data can be retrieved from a 2-D bar code on the exterior of the transmission case. This is done with the scan tool using the "Program Torque Converter Solenoid PI Curve" routine.

   Early build transmissions will have the 2-D barcode label on the right side of the transmission case. Late build transmissions will have the label attached to a machined pad at the top of the case, near the rear of the transmission. The data must be entered into the scan tool in order to upload the information to the PCM. In the event that the exterior BAR code is missing, or it is suspected that the valve body or TCC solenoid has been replaced without uploading the correct PI data into an existing PCM, the transmission oil pan must be removed to retrieve the information from the 2-D bar code on the body of the TCC solenoid.

   • 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. Refer to REMOVAL AND INSTALLATION .
   • With the scan tool, perform Quick Learn.
   • Perform the TRANSMISSION VERIFICATION TEST. Refer to TRANSMISSION VERIFICATION TEST .

1. The ignition must be off when performing a resistance check to find a short between circuits.
2. Isolate the circuit by disconnecting the Electronic Control Unit (ECU) and every component harness connector containing the circuit being tested. At this time leave all in-line connectors connected. Note:  Use the wiring diagram as a guide to follow the path of the circuit.
3. Connect one lead of the DVOM to the circuit being tested at the GPEC Diagnostic Adapter.
4. With the other lead of the DVOM probe all other circuits at the GPEC Diagnostic Adapter.

Is there continuity between the circuit being tested and any other circuit?

Yes 

• Repair the short between the circuits that have continuity. Use the wiring diagram as a guide to trace the circuits and look for any in-line connectors to help isolate the location of the short.
• Perform the TRANSMISSION VERIFICATION TEST. Refer to TRANSMISSION VERIFICATION TEST .

No 

• Go To  14

1. Turn the ignition off.
2. Remove and inspect the Transmission Oil Pan for excessive debris in accordance with the Service Information.
3. Remove and inspect the Primary Oil Filter in accordance with the Service Information.
   NOTE:

   Make sure the Primary Transmission Oil Filter and or O-ring is not cracked or split.

   Does the Oil Pan contain excessive debris and or is the Primary Oil Filter cracked or plugged?

   Yes 

   NOTE:

   This transmission is equipped with a solenoid for the Torque Converter Clutch (TCC) that is a Variable Force Solenoid (VFS) with close tolerance Pressure/Inductance (PI) curve. It is necessary to update the TCC solenoid PI data in the PCM when replacing the TCC solenoid, Valve Body or Transmission assembly. This is done with the scan tool using the "Program Torque Converter Solenoid PI Curve" routine. The PI data is located on a 2-D BAR code etched on the body of the TCC solenoid. The data must be entered into the scan tool in order to upload the information to the PCM.

   When replacing the TCC solenoid or Valve Body, obtain the PI data before installing the transmission oil pan. When replacing the transmission, the PI data can be obtained from a 2-D bar code on the exterior of the new transmission. Early build transmissions will have the 2-D barcode label on the right side of the transmission case. Late build transmissions will have the label attached to a machined pad at the top of the case, near the rear of the transmission. If it is suspected that the valve body or TCC VFS has been replaced without uploading the correct PI data into the PCM, the transmission oil pan must be removed to retrieve the information from the 2-D bar code on the body of the TCC solenoid.

   • Repair the plugged, cracked or split Primary Transmission Oil Filter and or O-ring. If the Primary Transmission Oil Filter is plugged, refer to the Service Information for the proper hydraulic repair procedure.
   • If the Valve Body or the TCC VFS solenoid is replaced, remove the external TCC VFS bar code label from the transmission case.
   • Perform the TRANSMISSION VERIFICATION TEST. Refer to TRANSMISSION VERIFICATION TEST .

   No 

   NOTE:

   This transmission is equipped with a solenoid for the Torque Converter Clutch (TCC) that is a Variable Force Solenoid (VFS) with close tolerance Pressure/Inductance (PI) curve. It is necessary to update the TCC solenoid PI data in the PCM when replacing the TCC solenoid, Valve Body or Transmission assembly. This is done with the scan tool using the "Program Torque Converter Solenoid PI Curve" routine. The PI data is located on a 2-D BAR code etched on the body of the TCC solenoid. The data must be entered into the scan tool in order to upload the information to the PCM.

   When replacing the TCC solenoid or Valve Body, obtain the PI data before installing the transmission oil pan. When replacing the transmission, the PI data can be obtained from a 2-D bar code on the exterior of the new transmission. Early build transmissions will have the 2-D barcode label on the right side of the transmission case. Late build transmissions will have the label attached to a machined pad at the top of the case, near the rear of the transmission. If it is suspected that the valve body or TCC VFS has been replaced without uploading the correct PI data into the PCM, the transmission oil pan must be removed to retrieve the information from the 2-D bar code on the body of the TCC solenoid.

   • Repair internal Transmission and inspect the Transmission Oil Pump in accordance with the Service Information and replace if necessary. If no problem is found, replace the Solenoid/TRS Assembly.
   • If the Valve Body or the TCC VFS solenoid is replaced, remove the external TCC VFS bar code label from the transmission case.
   • Perform the TRANSMISSION VERIFICATION TEST. Refer to TRANSMISSION VERIFICATION TEST .

Review the recorded Event Data and Environmental Data to see if P0868 set shortly after a restart (time since start less than 2 minutes).

Was the original P0868 fault set shortly after an engine restart?

Yes 

• Replace the cooler return (spin-on) filter in the transmission in accordance with the Service Information. Refer to STANDARD PROCEDURE .
• If the transmission oil cooler return filter was already replaced for this issue and the DTC returned, remove the transmission and replace the transmission oil pump assembly in accordance with the Service Information. Refer to REMOVAL AND INSTALLATION .
• Perform the TRANSMISSION VERIFICATION TEST. Refer to TRANSMISSION VERIFICATION TEST .

No 

• Go To  16

1. The conditions necessary to set the DTC are not present at this time.
2. Using the schematics as a guide, inspect the wiring and connectors specific to this circuit.
3. Wiggle the wires while checking for shorted and open circuits.
4. Check for any Service Bulletins that may apply.

   Were there any problems found?

   Yes 

   • Repair as necessary.
   • Perform the TRANSMISSION VERIFICATION TEST. Refer to TRANSMISSION VERIFICATION TEST .

   No 

   • Perform the TRANSMISSION VERIFICATION TEST. Refer to TRANSMISSION VERIFICATION TEST .
   • Test Complete.