2007 Compass Patriot MK Factory Service Manual 9 - ENGINE

P1115-GENERAL TEMPERATURE RATIONALITY

For a complete wiring diagram Refer to Section 8W.



Possible Causes
  
SENSOR SIGNAL CIRCUIT HIGH RESISTANCE
  
SENSOR GROUND CIRCUIT HIGH RESISTANCE
  
TEMPERATURE SENSOR
  
POWERTRAIN CONTROL MODULE (PCM)
  

Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. (Refer to 9 - ENGINE - STANDARD PROCEDURE).



Diagnostic Test

1. 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


No

2. 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


No

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


No

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


No

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


No

6. 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


No