P0652

P0652-SENSOR REFERENCE VOLTAGE 2 LOW

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

Theory of Operation

This sensor supply circuit provides a 5-Volt supply to: Camshaft Position Sensor, Inlet Air Temperature/Pressure Sensor, Exhaust Pressure Sensor, Fuel Pressure Sensor, Boost Pressure/CAC Temperature, EGR Valve, Fan Clutch Assembly, EGR Airflow Control Valve, and Crankcase Pressure Sensor. A MIL lamp will be lit immediately after this diagnostic runs and fails. The MIL lamp will turn off once the diagnostic runs and passes in four consecutive drive cycles.

- When Monitored:
With the key on.

- Set Condition:
Voltage detected on the 5-Volt supply circuit is below a calibrated value.





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

1. ACTIVE DIAGNOSTIC TROUBLE CODE (DTC)
1. Turn the ignition on.
2. Using the scan tool, record all Freeze frame data.
3. Using the scan tool, erase DTCs.
4. Turn the ignition off for 75 seconds.
5. Turn the ignition on.
6. Using the scan tool, read DTCs.

Did the DTC reset?

Yes

- Go To 2

No

- Perform the INTERMITTENT CONDITION diagnostic procedure. Intermittent Condition Test

2. CHECK THE CAMSHAFT POSITION SENSOR




1. Turn the ignition off.
2. Disconnect the Camshaft Position Sensor harness connector.
3. Turn the ignition on.
4. Measure the voltage on the (F857) 5-Volt Supply circuit at the Camshaft Position Sensor harness connector.

Is the voltage reading between 4.9 and 5.1 Volts?

Yes

- Replace the Camshaft Position Sensor.
- Perform the POWERTRAIN VERIFICATION TEST - 6.7L. Powertrain Verification Test.

No

- Go To 3

3. CHECK THE INLET AIR TEMPERATURE/PRESSURE SENSOR




1. Turn the ignition off.
2. Disconnect the Inlet Air Temperature/Pressure Sensor harness connector.
3. Turn the ignition on.
4. Measure the voltage on the (F857) 5-Volt Supply circuit at the Inlet Air Temperature/Pressure Sensor harness connector.

Is the voltage reading between 4.9 and 5.1 Volts?

Yes

- Replace the Inlet Air Temperature/Pressure Sensor.
- Perform the POWERTRAIN VERIFICATION TEST - 6.7L. Powertrain Verification Test.

No

- Go To 4

4. CHECK THE EXHAUST PRESSURE SENSOR




1. Turn the ignition off.
2. Disconnect the Exhaust Pressure Sensor harness connector.
3. Turn the ignition on.
4. Measure the voltage on the (F857) 5-Volt Supply circuit at the Inlet Exhaust Pressure Sensor harness connector.

Is the voltage reading between 4.9 and 5.1 Volts?

Yes

- Replace the Exhaust Pressure Sensor.
- Perform the POWERTRAIN VERIFICATION TEST - 6.7L. Powertrain Verification Test.

No

- Go To 5

5. CHECK THE FUEL RAIL PRESSURE SENSOR




1. Turn the ignition off.
2. Disconnect the Fuel Rail Pressure Sensor harness connector.
3. Turn the ignition on.
4. Measure the voltage on the (F857) 5-Volt Supply circuit at the Fuel Rail Pressure Sensor harness connector.

Is the voltage reading between 4.9 and 5.1 Volts?

Yes

- Replace the Fuel Rail Pressure Sensor in accordance with the Service Information.
- Perform the POWERTRAIN VERIFICATION TEST - 6.7L. Powertrain Verification Test.

No

- Go To 6

6. CHECK THE BOOST PRESSURE/CAC TEMPERATURE SENSOR




1. Turn the ignition off.
2. Disconnect the Boost Pressure/CAC Temperature Sensor harness connector.
3. Turn the ignition on.
4. Measure the voltage on the (F857) 5-Volt Supply circuit at the Boost Pressure/CAC Temperature Sensor harness connector.

Is the voltage reading between 4.9 and 5.1 Volts?

Yes

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

No

- Go To 7

7. CHECK THE EGR VALVE




1. Turn the ignition off.
2. Disconnect the EGR Valve harness connector.
3. Turn the ignition on.
4. Measure the voltage on the (F857) 5-Volt Supply circuit at the EGR Valve harness connector.

Is the voltage reading between 4.9 and 5.1 Volts?

Yes

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

No

- Go To 8

8. CHECK THE FAN SPEED SENSOR




1. Turn the ignition off.
2. Disconnect the Fan Clutch Assembly harness connector.
3. Turn the ignition on.
4. Measure the voltage on the (F857) 5-Volt Supply circuit at the Fan Clutch Assembly harness connector.

Is the voltage reading between 4.9 and 5.1 Volts?

Yes

- Replace the Fan Clutch Assembly.
- Perform the POWERTRAIN VERIFICATION TEST - 6.7L. Powertrain Verification Test.

No

- Go To 9

9. CHECK THE CRANKCASE PRESSURE SENSOR




1. Turn the ignition off.
2. Disconnect the Crankcase Pressure Sensor harness connector.
3. Turn the ignition on.
4. Measure the voltage on the (F857) 5-Volt Supply circuit at the Crankcase Pressure Sensor harness connector.

Is the voltage reading between 4.9 and 5.1 Volts?

Yes

- Replace the Crankcase Pressure Sensor.
- Perform the POWERTRAIN VERIFICATION TEST - 6.7L. Powertrain Verification Test.

No

- Go To 10

10. CHECK THE EGR AIRFLOW CONTROL VALVE
1. Turn the ignition off.
2. Disconnect the EGR Airflow Control Valve harness connector.
3. Turn the ignition on.
4. Measure the voltage on the (F857) 5-Volt Supply circuit at the EGR Airflow Control Valve harness connector.

Is the voltage reading between 4.9 and 5.1 Volts?

Yes

- Replace the EGR Airflow Control Valve.
- Perform the POWERTRAIN VERIFICATION TEST - 6.7L. Powertrain Verification Test.

No

- Go To 11

11. CHECK THE (F857) 5-VOLT SUPPLY CIRCUIT FOR A SHORT TO GROUND
1. Disconnect the PCM C1 harness connector.
2. Measure the resistance between ground and the (F857) 5-Volt Supply circuit at the PCM C1 harness connector.

Is the resistance below 10k Ohms?

Yes

- Repair the (F857) 5-Volt Supply circuit for a short to ground.
- Perform the POWERTRAIN VERIFICATION TEST - 6.7L. Powertrain Verification Test.

No

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