P007D

P007D-CHARGE AIR COOLER TEMPERATURE SENSOR CIRCUIT HIGH





For a complete wiring diagram refer to the Wiring Information Electrical Diagrams.

Theory of Operation

The Air Cooler Temperature Sensor (CAC) and the Boost Pressure Sensor are combined in one sensor and are located near the EGR Airflow Throttle Control Valve. The ECM provides a 5-volt reference voltage to the sensor. The ECM monitors the temperature of the air entering the intake using the CAC. At key on after an 8 hour cold soak, the CAC Temperature Sensor is compared to the Battery Temperature Sensor, Intake Temperature Sensor, and Coolant Temperature Sensor readings. If the temperatures differ more than a calibrated amount, a DTC is recorded. In the case that all four sensor values are distributed over a range of temperatures this diagnostic will not run. A block heater is one possible cause of such a condition. The key on monitor is disabled for ambient temperatures below 20°F. The rationality check looks at the temperature reading from the CAC Temperature Sensor over time and ensures that it changes. This monitor is used to verify the sensor is responding with temperature change. Both the key-on and rationality error require that the diagnostic fails in two consecutive drive cycles before the MIL lamp is lit. The ECM turns off the MIL lamp when the diagnostic runs and passes in 4 consecutive drive cycles.

- When Monitored:
With ignition on and battery voltage greater than 10.4 volts.

- Set Condition:
The circuit voltage to the ECM is above 4.78 for 5 seconds.





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

1. ACTIVE DTC

NOTE: If there are any 5-volt supply DTCs present, repair those DTCs before proceeding with this test.

1. Turn the ignition on.
2. With the scan tool, record all Freeze frame data.
3. With the scan tool, erase DTCs.
4. Turn the ignition off for 30 seconds.
5. Turn the ignition on.
6. With the scan tool, read DTCs.

Did the DTC reset?

Yes

- Go To 2

No

- Refer to the INTERMITTENT CONDITION - DIESEL (Diagnostic Procedure). Intermittent Condition Test

2. (K735) CHARGE AIR COOLER TEMPERATURE SENSOR SIGNAL CIRCUIT SHORTED TO VOLTAGE




1. Ignition on.
2. Disconnect the Air Cooler Temperature Sensor harness connector.

NOTE: Check connectors - Clean/repair as necessary.

3. With a volt meter connected to ground, measure the voltage of the (K735) Air Cooler Temperature Sensor Signal circuit at the harness connector.

Is there any voltage present?

Yes

- Repair the (K735) CAC Temperature Sensor Signal circuit for a short to voltage.
- Perform POWERTRAIN VERIFICATION TEST - 6.7L. Powertrain Verification Test

No

- Go To 3

3. (K735) CHARGE AIR COOLER TEMPERATURE SENSOR SIGNAL CIRCUIT OPEN




1. Turn the ignition off.
2. Disconnect the ECM C1 harness connector.
3. Measure the resistance of the (K735) CAC Temperature Sensor Signal circuit between the CAC Temperature Sensor harness connector and the ECM C1 harness connector.

Is the resistance below 10.0 ohms?

Yes

- Go To 4

No

- Repair the open or high resistance in the (K735) CAC Temperature Sensor Signal circuit.
- Perform POWERTRAIN VERIFICATION TEST - 6.7L. Powertrain Verification Test

4. (K916) CHARGE AIR COOLER TEMPERATURE SENSOR RETURN CIRCUIT OPEN




1. Measure the resistance of the (K916) CAC Temperature Sensor Return circuit between the CAC Temperature Sensor harness connector and the ECM C1 harness connector.

Is the resistance below 10.0 ohms?

Yes

- Go To 5

No

- Repair the open or high resistance in the (K916) Air Cooler Temperature Sensor Return circuit.
- Perform POWERTRAIN VERIFICATION TEST - 6.7L. Powertrain Verification Test

5. ECM




1. Reconnect the ECM C1 harness connector.
2. Turn the ignition on.
3. With the scan tool, erase DTCs.
4. While monitoring with scan tool, use a jumper wire and connect the (K735) CAC Temperature Sensor Signal circuit to the (K916) CAC Temperature Sensor Return circuit at the CAC harness connector.

Did the DTC P007C set?

Yes

- Replace the CAC/Boost Pressure Sensor.
- Perform POWERTRAIN VERIFICATION TEST - 6.7L. Powertrain Verification Test

No

- Replace the ECM.
- Perform POWERTRAIN VERIFICATION TEST - 6.7L. Powertrain Verification Test