Diagnostic Test
- ACTIVE DTC
- Turn the ignition off.
- If possible, allow the vehicle to sit with the ignition off for more than 480 minutes in an environment where the temperature is consistent and above -7° C (19.4° F).
- Test drive the vehicle. The vehicle must exceed 48 km/h (30 mph) during the test drive. Do not cycle the ignition off when the test drive is completed.
- With the scan tool, select View the DTCs.NOTE:
All ECT, Intake Air and Ambient Air Temperature Sensor codes must be diagnosed and repaired before continuing.
NOTE:In cold weather, this DTC could be set by a high powered block heater and no repair would be required.
Is the DTC Active or Pending at this time?
Yes
- Go To 2
No
- Perform the INTERMITTENT CONDITION diagnostic procedure. Refer to INTERMITTENT CONDITION .
- TEMPERATURE SENSOR CIRCUIT
- With the scan tool, read the ECT, Ambient Air Temp and Intake Air Temp Sensor temp values.
- Start the engine.
- Allow the engine to reach normal operating temperature while monitoring the three Sensor temperature values.
Is the temperature for each of the Sensors increasing properly?
Yes
- Perform the INTERMITTENT CONDITION diagnostic procedure. Refer to INTERMITTENT CONDITION .
No
- Go To 3
- TEMPERATURE SENSOR
- Disconnect the suspected sensor.
- Ignition on, engine not running.
- With the scan tool, read the voltage of the suspected Sensor.
- Connect a jumper wire between the Sensor Signal circuit and the Sensor ground circuit of the ECT Sensor, IAT Sensor and AAT Sensor.
Did the voltage reading start at 4.8 to 5.0 Volts and decrease to 0 Volts when the jumper wire was installed?
Yes
- Verify that there is good pin to terminal contact in the Sensor and Control Module connectors. If OK, replace the appropriate Temperature Sensor. Refer to SENSOR, COOLANT TEMPERATURE, REMOVAL or SENSOR, AIR TEMPERATURE, INTAKE, REMOVAL .
- Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
No
- Go To 4NOTE:
Remove the jumper wire before continuing.
- EXCESSIVE RESISTANCE IN THE TEMPERATURE SENSOR SIGNAL CIRCUIT
- Turn the ignition off.
- Disconnect the PCM C2 harness connector.
- Disconnect the TIPM C4 harness connector.
- Measure the resistance of the Sensor Signal circuit from the Sensor harness connector to the appropriate terminal of PCM C2 harness connector for the ECT Sensor and IAT Sensor.
- Measure the resistance of the (G31) AAT Sensor Signal circuit from the Sensor harness connector to the TIPM C4 harness connector.
Is the resistance above 5.0 Ohms?
Yes
- Repair the excessive resistance in the Temperature Sensor Signal circuit.
- Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
No
- Go To 5
- EXCESSIVE RESISTANCE IN THE SENSOR GROUND CIRCUIT
- Measure the resistance of the (K900) Sensor ground circuit from the ECT Sensor and IAT Sensor to the appropriate terminal of PCM harness
- Measure the resistance of the (G931) Sensor ground circuit from the AAT Sensor harness connector to the TIPM C4 harness connector.
Is the resistance above 5.0 Ohms?
Yes
- Repair the excessive resistance in the Sensor ground circuit.
- Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
No
- Go To 9
- SENSOR SIGNAL CIRCUIT SHORTED TO GROUND
- Measure the resistance between ground and the Sensor Signal circuit at the Sensor harness connector.
Is the resistance below 100 Ohms?
Yes
- Repair the short to ground in the Sensor Signal circuit.
- Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
No
- Go To 7
- Measure the resistance between ground and the Sensor Signal circuit at the Sensor harness connector.
- SENSOR SIGNAL CIRCUIT SHORTED TO THE SENSOR GROUND CIRCUIT
- Measure the resistance between Sensor Ground and the Sensor Signal circuit at the Sensor harness connector.
Is the resistance below 100 Ohms?
Yes
- Repair the short between the Sensor ground circuit and the Sensor Signal circuit.
- Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
No
- Go To 8
- Measure the resistance between Sensor Ground and the Sensor Signal circuit at the Sensor harness connector.
- SENSOR SIGNAL CIRCUIT SHORTED TO VOLTAGE
- Turn the ignition on.
- Measure the voltage on the Sensor Signal circuit at the Sensor harness connector.
Is there any voltage present?
Yes
- Repair the short to voltage in the Sensor Signal circuit.
- Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
No
- Go To 9
- POWERTRAIN CONTROL MODULE (PCM)
- Turn the ignition off.
- Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the related Sensors and the Powertrain Control Module (PCM).
- Look for any chafed, pierced, pinched or partially broken wires.
- Look for broken, bent, pushed out or corroded terminals. Verify that there is good pin to terminal contact in the related Sensor and Powertrain Control Module connectors.
- Perform any Technical Service Bulletins that may apply.
Were there any problems found?
Yes
- Repair as necessary.
- Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
No
- Replace and program the Powertrain Control Module in accordance with the Service Information. Refer to MODULE, POWERTRAIN CONTROL, REMOVAL .
- Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .