NGC
P0073-AMBIENT AIR TEMPERATURE SENSOR CIRCUIT HIGH
For a complete wiring diagram Consult Diagrams/Electrical
- When Monitored:
With the ignition on and battery voltage greater than 10.4 volts.
- Set Condition:
The PCM detects that the Ambient Air Temperature Sensor input voltage is above the maximum acceptable value.
Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding.Initial Inspection and Diagnostic Overview
Diagnostic Test
1. DTC IS ACTIVE
NOTE: Diagnose any CAN - C Communication DTCs before continuing.
NOTE: Diagnose and repair any system voltage DTCs before continuing with this test.
Start the engine and allow it to reach normal operating temperature.
WARNING: When the engine is operating, do not stand in direct line with the fan. Do not put your hands near the pulleys, belts, or fan. Do not wear loose clothing. Failure to follow these instructions can result in personal injury or death.
With the scan tool, select View DTCs.
Is the DTC Active at this time?
Yes
- Go to 2
No
- Refer to the *CHECKING FOR AN INTERMITTENT DTC Diagnostic Procedure. Checking For An Intermittent DTC
2. (G31) AAT SIGNAL CIRCUIT SHORTED TO VOLTAGE
Turn the ignition off.
Disconnect the Ambient Air Temperature Sensor connector.
Disconnect the C4 Totally Integrated Power Module (TIPM) connector.
Turn the ignition on.
Measure the voltage of the (G31) AAT Signal circuit in the Ambient Air Temperature Sensor harness connector.
Is there any voltage present?
Yes
- Repair the short to voltage in the (G31) AAT Signal circuit.
- Perform the PCM Verification Test. Powertrain Verification Test
No
- Go to 3
3. (G31) AAT SIGNAL CIRCUIT OPEN
Turn the ignition off.
Measure the resistance of the (G31) AAT Signal circuit between the Ambient Air Temperature Sensor harness connector and the C4 Totally Integrated Power Module (TIPM) harness connector.
Is the resistance below 5.0 ohms?
Yes
- Go to 4
No
- Repair the open in the (G31) AAT Signal circuit.
- Perform the PCM Verification Test. Powertrain Verification Test
4. (G931) AAT SENSOR GROUND CIRCUIT OPEN
Measure the resistance of the (G931) AAT Sensor Ground circuit between the Ambient Air Temperature Sensor harness connector and the C4 TIPM harness connector.
Is the resistance below 5.0 ohms?
Yes
- Go to 5
No
- Repair the open in the (G931) AAT Sensor Ground circuit.
- Perform the PCM Verification Test. Powertrain Verification Test
5. AMBIENT AIR TEMPERATURE SENSOR
Turn the ignition off.
Connect the C4 Totally Integrated Power Module (TIPM) harness connector.
Connect a jumper wire between the (G31) AAT Signal circuit and the (G931) AAT Sensor Ground in the Ambient Air Temperature Sensor harness connector.
Turn the ignition on.
With the scan tool, read the Ambient Air Temperature Sensor signal voltage.
Is the voltage below 1.0 volt with the jumper wire in place?
Yes
- Verify that there is good pin to terminal contact in the AAT Sensor and Totally Integrated Power Module connectors. Replace the Ambient Air Temperature Sensor if no problems were found with the connectors.
- Perform the PCM Verification Test. Powertrain Verification Test
No
- Go to 6
6. TOTALLY INTEGRATED POWER MODULE (TIPM)
Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the Ambient Air Temperature Sensor and the Totally Integrated Power Module (TIPM).
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 AAT Sensor and Totally Integrated Power Module connectors.
Monitor the scan tool data relative to this circuit and wiggle test the wiring and connectors.
Look for the data to change or for the DTC to reset during the wiggle test.
Search for any Technical Service Bulletins that may apply.
Were any problems found?
Yes
- Repair as necessary.
- Perform the PCM Verification Test. Powertrain Verification Test
No
- Replace and program the Totally Integrated Power Module (TIPM).
- Perform the PCM Verification Test. Powertrain Verification Test