Diagnostic Test
- CHECK FOR AN ACTIVE CONDITION
- With the scan tool, read all DTCs and record on the repair order.
- Start the Engine with the Shift Lever in PARK.
- With the scan tool, read the Transmission Output and Input Speed Sensor states.
Is the Output Speed Sensor reading twice the Input Speed Sensor reading?
Yes
- Go To 2
No
- Perform the TESTING FOR AN INTERMITTENT CONDITION procedure. Refer to TESTING FOR AN INTERMITTENT CONDITION .
- ISOLATE AND CHECK THE (T13) SENSOR GROUND CIRCUIT FOR AN OPEN/HIGH RESISTANCE CAUTION:
Do not probe the PCM harness connectors. Probing the PCM harness connectors will damage the PCM terminals resulting in poor terminal to pin connection. Install the GPEC Diagnostic Adaptor to perform the diagnosis.
- Connect the (special tool #10436, Adapter, GPEC Diagnostic) to the appropriate PCM harness connector.
- Important:
The GPEC Diagnostic Adapter can add up to 1.5 Ohms of resistance to the circuit.
- The ignition must be off when checking the continuity of a circuit.
- 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.
- 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.
- Connect one lead of the DVOM to the circuit being tested at the component harness connector.
- 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 3
No
- Repair the circuit for an open or high resistance.
- Perform the TRANSMISSION VERIFICATION TEST. Refer to TRANSMISSION VERIFICATION TEST .
- ISOLATE AND CHECK THE (T13) SENSOR GROUND CIRCUIT FOR A SHORT TO GROUND CAUTION:
Do not probe the PCM harness connectors. Probing the PCM harness connectors will damage the PCM terminals resulting in poor terminal to pin connection. Install the GPEC Diagnostic Adaptor to perform the diagnosis.
- The ignition must be off when checking a circuit for continuity to ground.
- 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.
- Connect the negative lead of the DVOM to a known good ground.
- 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 4
- ISOLATE AND CHECK THE (T13) SENSOR GROUND CIRCUIT FOR A SHORT TO VOLTAGE CAUTION:
Do not probe the PCM harness connectors. Probing the PCM harness connectors will damage the PCM terminals resulting in poor terminal to pin connection. Install the GPEC Diagnostic Adaptor to perform the diagnosis.
- Turn the ignition off.
- Isolate the circuit by disconnecting the ECM connector 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.
- Turn the ignition switch to the RUN position, engine off.
- Connect the negative lead of the DVOM to a known good ground.
- With the positive lead of the DVOM, probe the circuit being tested at GPEC Diagnostic Adapter and check for any voltage present in the circuit.
NOTE:There should be no voltage present in the circuit being tested.
Is there voltage present in the circuit being tested?
Yes
- Repair the circuit for a short to voltage. 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
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 .