Diagnostic Test.
- ACTIVE DTC
- Turn the ignition on.
- With a scan tool, select View DTCs.NOTE:
Diagnose and repair any AAT, ECT, and IAT sensor DTCs before continuing with this test.
NOTE:Diagnose and repair P1607 PCM INTERNAL SHUTDOWN TIMER SLOW RATIONALITY or P2610 PCM INTERNAL SHUTDOWN TIMER FAST RATIONALITY if either code is set before continuing with this test.
NOTE:Using an unapproved block heater in cold temperatures may cause this DTC to set. No repair is required.
Is the status Active for this DTC?
Yes
- Go To 2
No
- Perform the CHECKING FOR AN INTERMITTENT DTC Diagnostic Procedure. Refer to INTERMITTENT CONDITION .
- TEMPERATURE SENSOR CIRCUIT VALUE IMPLAUSIBLE NOTE:
Allow the engine sit for 6 - 8 hours before testing.
- With a scan tool, monitor the AAT, ECT, and IAT sensor values.
- Start the engine.
- Allow the engine to reach normal operating temperature.
Does the value for each of the sensors increase smoothly and as expected?
Yes
- Perform the CHECKING FOR AN INTERMITTENT DTC Diagnostic Procedure. Refer to INTERMITTENT CONDITION .
No
- Go To 3
- TEMPERATURE SENSOR NOTE:
If it is necessary to replace the AAT sensor, be sure to drive the vehicle over 30 MPH for at least 5 minutes to update the AAT value.
- Turn the ignition on.
- Disconnect the harness connector for the sensor that had a value which did not increase smoothly and as expected.
- With the scan tool, read the sensor voltage with the connected disconnected.NOTE:
The sensor voltage should be approximately 5.0 volts with the connector disconnected.
- Connect a jumper wire between the sensor signal circuit and the sensor ground circuit in the harness connector.
- With the scan tool, read the sensor voltage with the jumper wire in place.NOTE:
The sensor voltage should be approximately 0 volts with the jumper wire in place.
Does the sensor voltage change as described?
Yes
- Replace the sensor.
- Perform the PCM VERIFICATION TEST. Refer to PCM VERIFICATION TEST .
No
- Go To 4
- SENSOR SIGNAL CIRCUIT HIGH RESISTANCE
- Turn the ignition off.
- For the AAT sensor, disconnect the TIPM harness connector. Otherwise disconnect the PCM harness connector.
- Measure the resistance of the sensor signal circuit from the sensor harness connector to the module harness connector.
Is the resistance above 5.0 Ohms?
Yes
- Repair the sensor signal circuit for high resistance.
- Perform the PCM VERIFICATION TEST. Refer to PCM VERIFICATION TEST .
No
- Go To 5
- SENSOR GROUND CIRCUIT HIGH RESISTANCE
- Measure the resistance of the sensor ground circuit from the sensor harness connector to the module harness connector.
Is the resistance above 5.0 Ohms?
Yes
- Repair the sensor ground circuit for high resistance.
- Perform the PCM VERIFICATION TEST. Refer to PCM VERIFICATION TEST .
No
- Go To 6
- Measure the resistance of the sensor ground circuit from the sensor harness connector to the module harness connector.
- POWERTRAIN CONTROL MODULE (PCM)
- Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the sensor 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.
- 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.
- Refer to any Technical Service Bulletins that may apply.
Were any problems found?
Yes
- Repair as necessary.
- Perform the PCM VERIFICATION TEST. Refer to PCM VERIFICATION TEST .
No
- Replace and program the Powertrain Control Module per Service Information. Refer to MODULE, POWERTRAIN CONTROL, REMOVAL .
- Perform the PCM VERIFICATION TEST. Refer to PCM VERIFICATION TEST .