WOMS
P code powertrain Medium severity

P1625 B+ Supply To VCRM Fan Circuit Malfunction

The OBD2 code P1625 indicates a malfunction in the B+ supply to the Vehicle Control Relay Module (VCRM) fan circuit, which may affect the operation of the cooling fan system

Definition

The OBD2 code P1625 indicates a malfunction in the B+ supply to the Vehicle Control Relay Module (VCRM) fan circuit, which may affect the operation of the cooling fan system

Common causes

  • Faulty VCRM (Variable Control Relay Module)
  • Damaged wiring or connectors in the fan circuit
  • Blown fuse related to the fan circuit
  • Short circuit in the fan circuit
  • Malfunctioning engine control module (ECM)
  • Poor ground connection
  • Faulty fan motor

Common misdiagnoses

  • Faulty VCRM (Variable Control Relay Module)
  • Bad fan motor
  • Wiring issues or shorts in the fan circuit
  • Faulty engine control module (ECM)
  • Incorrectly diagnosed overheating issues
  • Malfunctioning temperature sensors
  • Battery or charging system problems
  • Issues with the cooling system (e.g., low coolant)

Troubleshooting steps

  1. 1. Check the Battery and Charging System

    Ensure the battery is fully charged and in good condition

  2. 2. Check the alternator output to ensure it is providing adequate voltage (typically around 13.5 to 14.5 volts)

  3. 3. Inspect Fuses and Relays

    Check the fuses related to the cooling fan and VCRM. Replace any blown fuses

  4. 4. Inspect the relays associated with the cooling fan circuit. Test or replace any faulty relays

  5. 5. Examine Wiring and Connectors

    Inspect the wiring harness and connectors for any signs of damage, corrosion, or loose connections

  6. 6. Pay special attention to the wiring leading to the VCRM and the cooling fan

  7. 7. Test the VCRM

    If accessible, test the Variable Control Relay Module for proper operation. This may involve checking for continuity and proper voltage at the input and output terminals

  8. 8. If the VCRM is faulty, it may need to be replaced

  9. 9. Check the Cooling Fan

    Test the cooling fan itself to ensure it operates correctly. You can do this by applying direct power to the fan to see if it spins

  10. 10. If the fan does not operate, it may need to be replaced

  11. 11. Scan for Additional Codes

    Use an OBD-II scanner to check for any additional trouble codes that may provide more context or indicate related issues

  12. 12. Inspect the Engine Control Module (ECM)

    In some cases, the issue may be related to the ECM. Check for any software updates or known issues with the ECM that could affect the VCRM operation

  13. 13. Perform a Visual Inspection

    Look for any signs of overheating, burnt components, or other physical damage in the engine bay that could affect the cooling system

  14. 14. Clear Codes and Test Drive

    After performing repairs, clear the trouble codes and take the vehicle for a test drive to see if the code returns