Totally Integrated Power Module (TIPM)

P0072-AMBIENT AIR TEMPERATURE SENSOR CIRCUIT LOW





For a complete wiring diagram, refer to the Wiring Information.

- When Monitored:
With the ignition on.

Battery voltage greater than 10.4 volts.

- Set Condition:
The Totally Integrated Power Module (TIPM) detects the Ambient Air Temperature Sensor input voltage is below the minimum acceptable value.





1. VERIFY THE DTC IS ACTIVE

NOTE: Diagnose and repair any system voltage DTCs before continuing with this test.

1. 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 may result in possible serious or fatal injury.

2. With the scan tool, select View DTCs.

Is the DTC Active at this time?

Yes

- Go To 2

No

- Test complete, the condition or conditions that originally set this DTC are not present at this time. Using the wiring diagrams as a guide, check all related splices and connectors for signs of water intrusion, corrosion, pushed out or bent terminals, and correct pin tension.
- Perform the BODY VERIFICATION TEST. Body Verification Test.

2. CHECK THE AMBIENT AIR TEMPERATURE SENSOR
1. Turn the ignition off.
2. Disconnect the Ambient Air Temperature Sensor harness connector.
3. Turn the ignition on.
4. With the scan tool, read the Ambient Air Temperature Sensor signal voltage.

Is the voltage above 4.5 volts with the Ambient Air Temperature Sensor harness disconnected?

Yes

- Verify there is good pin to terminal contact in the AAT Sensor and TIPM harness connectors. Replace the Ambient Temperature Sensor if no problems were found with the connectors. Ambient Temperature Sensor - Removal.
- Perform the BODY VERIFICATION TEST. Body Verification Test.

No

- Go To 3

3. CHECK THE (G31) AAT SENSOR SIGNAL CIRCUIT FOR A SHORT TO GROUND




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

Is the resistance above 10k Ohms?

Yes

- Go To 4

No

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

4. CHECK THE (G31) AAT SENSOR SIGNAL CIRCUIT FOR A SHORT TO THE (G931) SENSOR RETURN CIRCUIT




1. Measure the resistance between the (G31) AAT Sensor Signal circuit and the (G931) Sensor Return circuit in the Ambient Air Temperature Sensor harness connector.

Is the resistance above 10k Ohms?

Yes

- Go To 5

No

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

5. TOTALLY INTEGRATED POWER MODULE (TIPM)
1. 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).
2. Look for any chafed, pierced, pinched, or partially broken wires.
3. Look for broken, bent, pushed out or corroded terminals.
4. Verify that there is good pin to terminal contact in the AAT Sensor and TIPM connectors.
5. Monitor the scan tool data relative to this circuit and wiggle test the wiring and connectors.
6. Look for the data to change or for the DTC to reset during the wiggle test.
7. Perform any Technical Service Bulletins (TSB)s that may apply.

Were any problems found?

Yes

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

No

- Replace the TIPM. Totally Integrated Power Module (TIPM) - Removal.
- Perform the BODY VERIFICATION TEST. Body Verification Test.