Totally Integrated Power Module (TIPM)

P0072-AMBIENT AIR TEMPERATURE SENSOR CIRCUIT LOW



- When Monitored:
With the ignition on. Battery voltage greater than 10.4 volts.

- Set Condition:
The Ambient Air Temperature (AAT) sensor circuit voltage at the Totally Integrated Power Module (TIPM) is less than 0.078 of a volt for more than 2.8 seconds. One Trip Fault. Three good trips to clear the MIL.





Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. Pre-Diagnostic Troubleshooting Procedure.

1. AAT SENSOR VOLTAGE BELOW 0.078 OF A VOLT
1. Ignition on, engine not running.
2. With a scan tool, read the AAT voltage.

Is the voltage below 0.078 of a volt?

Yes

- Go To 2

No

- Perform the CHECKING FOR AN INTERMITTENT DTC diagnostic procedure. Intermittent Condition Test.

2. AAT SENSOR
1. Turn the ignition off.
2. Disconnect the AAT harness connector.
3. Ignition on, engine not running.
4. With a scan tool, read AAT voltage.

Is the voltage above 1.0 volt?

Yes

- Replace the AAT Sensor.
- Perform the BODY VERIFICATION TEST. Body Verification Test.

No

- Go To 3

3. (G31) AAT SIGNAL CIRCUIT SHORTED TO THE (G931) AAT RETURN CIRCUIT




1. Turn the ignition off.
2. Disconnect the C4 TIPM harness connector.
3. Measure the resistance between the (G931) AAT Return circuit and the (G31) AAT Signal circuit in the AAT Sensor harness connector.

Is the resistance below 1000 ohms?

Yes

- Repair the short to between the (G931) AAT Return circuit and the (G31) AAT Signal circuit.
- Perform the BODY VERIFICATION TEST. Body Verification Test.

No

- Go To 4

4. (G31) AAT SIGNAL CIRCUIT SHORTED GROUND




1. Measure the resistance between ground and the (G31) AAT Signal circuit in the AAT Sensor harness connector.

Is the resistance below 1000 ohms?

Yes

- Repair the short to ground in the (G31) AAT Signal circuit.
- Perform the BODY VERIFICATION TEST. Body Verification Test.

No

- Go To 5

5. TOTALLY INTEGRATED POWER MODULE (TIPM)

NOTE: Before continuing, check the TIPM harness connector terminals for corrosion, damage, or terminal push out. Repair as necessary.

1. Using the schematics as a guide, inspect the wire harness and connectors. Pay particular attention to all Power and Ground circuits.

Were there any problems found?

Yes

- Repair as necessary.
- Perform the BODY VERIFICATION TEST. Body Verification Test.

No

- Replace and program the Totally Integrated Power Module.
- Perform the BODY VERIFICATION TEST. Body Verification Test.