P007C

P007C-CHARGE AIR COOLER TEMPERATURE SENSOR CIRCUIT LOW





For complete wiring diagrams refer to Diagrams/Electrical.


Theory of Operation

The intake manifold temperature sensor is a variable resistor sensor and is used to measure the temperature of the air entering the intake manifold of the engine. The ECM supplies 5-volts to the intake manifold temperature signal circuit. The ECM monitors the change in voltage caused by changes in the resistance of the sensor to determine the intake manifold temperature. The intake manifold temperature sensor is a combination sensor that also reads pressure. It is located on the intake manifold. The MIL lamp is illuminated immediately when the diagnostic runs and fails. During this time the customer may notice periods of white smoke as well as the fan running more often. The MIL lamp is turned off once the diagnostic runs and passes in 4 consecutive drive cycles.

- When Monitored:

The ECM monitors the change in signal voltage and converts this to a temperature value.

- Set Condition:

The ECM illuminates the MIL light immediately when the diagnostic runs and fails. During this time it uses an estimated value for Inlet Air Temperature. The ECM will turn off the MIL after the diagnostic runs and passes in 4 consecutive drive cycles.







Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding.


1. INTAKE AIR TEMP SENSOR OUT OF SPECIFICATION

Disconnect the Intake Air Temperature sensor harness connector.


NOTE: Check connectors - Clean/repair as necessary.

Measure the resistance of the Intake Air Temp sensor.

Is the resistance between 300 and 90k ohms?

Yes

- Go To2

No

- Replace the Intake Air Temperature Sensor/MAP sensor.
- Perform POWERTRAIN VERIFICATION TEST. Powertrain Verification Test

2. INTERMITTENT CONDITION

Reconnect the circuit.

Turn the ignition on.

With the scan tool, erase DTCs.

With the scan tool, read DTCs.

Did the DTC reappear?

Yes

- Refer to the INTERMITTENT CONDITION Diagnostic Procedure. Intermittent Condition

No

- Go To3

3. (K21) SIGNAL CIRCUIT SHORTED TO GROUND CIRCUIT





Turn the ignition off.

Disconnect the ECM harness connector.


NOTE: Check connectors - Clean/repair as necessary.

Measure the resistance between the engine ground and the (K21) temperature sensor signal circuit at the sensor harness connector.

Is the resistance more than 100 k ohms?

Yes

- Go To4

No

- Repair the (K21) temperature sensor signal circuit.
- Perform POWERTRAIN VERIFICATION TEST. Powertrain Verification Test

4. WIRING HARNESS SHORTED





Measure the resistance between the (K21) signal circuit and all other circuits at the ECM harness connector.

Is the resistance more than 100 k ohms?

Yes

- Go To5

No

- Repair as necessary.
- Perform POWERTRAIN VERIFICATION TEST. Powertrain Verification Test

5. (F855) 5-VOLT SUPPLY CIRCUIT SHORTED TO (K916) RETURN CIRCUIT





Reconnect the ECM harness connector connected.

Turn the ignition on.

Measure the voltage between the (F855) 5-volt supply circuit and the (K916) return circuit the sensor harness connector.

Is the voltage between 4.5 and 5.5 volts?

Yes

- Go To7

No

- Go To6

6. (F855) 5-VOLT SUPPLY CIRCUIT OPEN





Turn the ignition off.

Disconnect the ECM harness connector.

Measure the voltage at the (F855) 5-volt supply circuit of the sensor harness connector.

Is the voltage between 4.5 and 5.5 volts?

Yes

- Repair the open (F855) 5-volt supply circuit.
- Perform POWERTRAIN VERIFICATION TEST. Powertrain Verification Test

No

- Go To7

7. ECM

Reconnect the ECM harness connector.

Reconnect the intake air temp sensor harness connector.

Turn the ignition on.

While monitoring with scan tool, disconnect the temperature sensor

Did the DTC P0113 set?

Yes

- Clear DTC's, repair complete.
- Perform POWERTRAIN VERIFICATION TEST. Powertrain Verification Test

No

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