P2743
P2743-TRANSMISSION FLUID TEMPERATURE SENSOR 2 HIGH
For a complete wiring diagram, refer to the Wiring Information.
Theory of Operation
The Torque Converter Out Oil Temperature sensor is used to determine if the transmission needs to go into high temperature shift strategy to protect the transmission.
When Monitored:
- Ignition on, the engine running.
Set Condition:
- The Diagnostic Trouble code (DTC) will set if the monitored Transmission Temperature Sensor Signal circuit is greater than -50° C (-58° F) for more than 500 ms.
Always perform the AS68RC Pre-Diagnostic Troubleshooting procedure before proceeding. AS68RC Pre-Diagnostic Troubleshooting Procedure
1. CHECK IF DTC IS CURRENT
1. Using the scan tool, read TCM DTCs.
2. Record the Environmental Data and any DTCs.
3. Clear DTCs.
4. Using the recorded 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 reset?
Yes
- Go To 2
No
- Go To 6
2. CHECK THE (T819) TORQUE CONVERTER OUT OIL TEMPERATURE SENSOR SIGNAL CIRCUIT FOR A SHORT TO VOLTAGE
1. Turn the ignition off to the lock position.
2. Disconnect the TCM C2 harness connectors.
3. Disconnect the Torque Converter Out Oil Temperature sensor harness connector.
4. Ignition on, engine not running.
5. Measure the voltage of the (T819) Torque Converter Out Oil Temperature Signal circuit in the TCM C2 harness connector.
Is the voltage above 0.5 of a volt?
Yes
- Repair the (T819) Torque Converter Out Oil Temperature Signal circuit for a short to voltage.
- Perform AS68RC TRANSMISSION VERIFICATION TEST AS68RC Transmission Verification Test.
No
- Go To 3
3. CHECK THE (T819) TORQUE CONVERTER OUT OIL TEMPERATURE SENSOR SIGNAL CIRCUIT FOR AN OPEN
1. Measure the resistance of the (T819) Torque Converter Out Oil Temperature Signal circuit between the TCM C2 harness connector and the Torque Converter Out Oil Temperature sensor harness connector.
Is the resistance below 5.0 Ohms?
Yes
- Go To 4
No
- Repair the (T819) Torque Converter Out Oil Temperature Signal circuit for an open.
- Perform AS68RC TRANSMISSION VERIFICATION TEST AS68RC Transmission Verification Test.
4. CHECK THE (T820) SENSOR GROUND CIRCUIT FOR AN OPEN
1. Measure the resistance of the (T820) Sensor Ground circuit between the TCM C3 harness connector and the Torque Converter Out Oil Temperature sensor harness connector.
Is the resistance below 5.0 Ohms?
Yes
- Go To 5
No
- Repair the (T820) Sensor Ground circuit for an open.
- Perform AS68RC TRANSMISSION VERIFICATION TEST AS68RC Transmission Verification Test.
5. CHECK THE TRANSMISSION TEMPERATURE SENSOR
1. Turn the ignition off to the lock position.
2. Reconnect the Torque Converter Out Oil Temperature sensor harness connector.
3. Disconnect the TCM C2 and C3 harness connector.
NOTE: Check connectors - Clean/repair as necessary
4. Measure the resistance of the Torque Converter Out Oil Temperature sensor between the (T819) Torque Converter Out Oil Temperature Signal circuit in the TCM C2 and the (T820) Sensor Ground circuit in the TCM C3 harness connector.
5. Using the chart at the chart above, compare the Temperature Sensor temperature to the correlating resistance value.
Is the resistance within the specified range when the sensor is at the given temperature?
Yes
- Using the schematics as a guide, check the Transmission Control Module (TCM) pins, terminals, and connectors for corrosion, damage, or terminal push out. Pay particular attention to all power and ground circuits. If no problems are found, replace and program the TCM.
- Perform AS68RC TRANSMISSION VERIFICATION TEST AS68RC Transmission Verification Test.
No
- Replace the Transmission Temperature Sensor.
- Perform AS68RC TRANSMISSION VERIFICATION TEST AS68RC Transmission Verification Test.
6. CHECK WIRING AND CONNECTORS
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 AS68RC TRANSMISSION VERIFICATION TEST AS68RC Transmission Verification Test.
No
- Test Complete.