P0652 LOW VOLTAGE AT THE #1 SENSOR SUPPLY CIRCUIT

When Monitored and Set Condition:

When Monitored: With the key on.
Set Condition: Voltage detected on the sensor supply is below a calibrated value.

POSSIBLE CAUSES

• ECM
• (F855) #1 5-VOLT SUPPLY SHORTED TO GROUND
• (F855) #1 5-VOLT SUPPLY SHORTED
• FUEL RAIL PRESSURE
• A/C PRESSURE SENSOR
• MAP SENSOR
• CAMSHAFT POSITION SENSOR
• INTERMITTENT CONDITION

DIAGNOSTIC PROCEDURE

1. Turn the ignition off. Disconnect the ECM 60 pin harness connector.
   NOTE: Check connectors - Clean/repair as necessary.
   Turn the ignition on. Measure the voltage between the Sensor (F855) #1 5-volt Supply and the Sensor (K916) #1 Return pin at the ECM. Is the voltage between 4.5 and 5.5 volts?
   Yes --> Go To 2
   No --> Replace and program the ECM in accordance with the Service Information. Perform POWERTRAIN VERIFICATION TEST VER - 1 (DIESEL).
2. Disconnect the Pressure sensors harness connectors and the engine position sensor. Measure the resistance between the (P855) #1 sensor supply circuits at the ECM harness connector and battery negative. Is the resistance greater than 100K Ohms?
   Yes --> Go To 3
   No --> Repair the harness. Perform POWERTRAIN VERIFICATION TEST VER - 1 (DIESEL).
3. Reconnect the ECM harness connector. While monitoring with the DRBIII®, disconnect the fuel rail pressure sensor. Is DTC P0652 set?
   Yes --> Go To 4
   No --> Replace the Fuel rail pressure sensor. Perform POWERTRAIN VERIFICATION TEST VER - 1 (DIESEL).
4. While monitoring with the DRBIII®, disconnect the A/C pressure sensor. Is DTC P0652 set?
   Yes --> Go To 5
   No --> Replace the A/C pressure sensor. Perform POWERTRAIN VERIFICATION TEST VER - 1 (DIESEL).
5. While monitoring with the DRBIII®, disconnect the map sensor. Is DTC P0652 set?
   Yes --> Go To 6
   No --> Replace the MAP sensor. Perform POWERTRAIN VERIFICATION TEST VER - 1 (DIESEL).
6. While monitoring with the DRBIII®, disconnect the Camshaft position sensor. Is DTC P0652 set?
   Yes --> Go To 7
   No --> Replace the Camshaft position sensor. Perform POWERTRAIN VERIFICATION TEST VER - 1 (DIESEL).
7. Measure the resistance between the (F855) #1 sensor supply circuit of the ECM harness connector and all other circuits in both ECM harness connectors. Is the resistance greater than 100K Ohms?
   Yes --> Refer to the SYMPTOM: INTERMITTENT CONDITION Symptom (Diagnostic Procedure). Perform POWERTRAIN VERIFICATION TEST VER - 1 (DIESEL).
   No --> Repair the shorted circuit. Perform POWERTRAIN VERIFICATION TEST VER - 1 (DIESEL).