P0652: Malfunction Indicator Lamp (MIL) Control Circuit Low

Definition

The OBD2 code P0652 indicates a malfunction in the Malfunction Indicator Lamp (MIL) control circuit, specifically that the circuit is reading a low voltage or signal, which may prevent the MIL from functioning properly

Common causes

Faulty Engine Control Module (ECM)
Short circuit in the MIL control circuit
Open circuit in the MIL control circuit
Damaged wiring or connectors
Faulty MIL indicator bulb
Poor ground connection
Corroded connectors or terminals

Common misdiagnoses

Faulty Engine Control Module (ECM)
Wiring issues or shorts in the MIL circuit
Faulty MIL indicator light
Issues with the instrument cluster
Faulty sensors or actuators related to the MIL
Poor ground connections
Incorrectly installed or damaged connectors

Troubleshooting steps

1. Check the Vehicle's Battery and Charging System
2. Ensure the battery is fully charged and in good condition
3. Check the alternator and charging system to ensure they are functioning properly
4. Inspect the MIL Bulb
5. Verify that the MIL (check engine light) bulb is not burned out. If it is, replace it and clear the code to see if it returns
6. Examine the Wiring and Connectors
7. Inspect the wiring and connectors related to the MIL circuit for any signs of damage, corrosion, or loose connections
8. Pay special attention to the wiring harness that connects to the Engine Control Module (ECM)
9. Check the Ground Connections
10. Ensure that all ground connections related to the ECM and MIL circuit are secure and free of corrosion
11. Test the MIL Control Circuit
12. Use a multimeter to check the voltage and continuity of the MIL control circuit. Compare your findings with the specifications in the vehicle's service manual
13. If the voltage is low or there is no continuity, trace the circuit to find the fault
14. Inspect the ECM
15. If all other components check out, the issue may lie within the Engine Control Module itself. Check for any software updates or reprogramming that may be needed
16. In some cases, the ECM may need to be replaced if it is determined to be faulty
17. Clear the Code and Test Drive
18. After performing repairs, clear the code using an OBD-II scanner and take the vehicle for a test drive to see if the code returns
19. Consult Technical Service Bulletins (TSBs)
20. Check for any TSBs related to the P0652 code for your specific make and model, as there may be known issues or fixes
21. Seek Professional Help
22. If you are unable to resolve the issue after these steps, consider seeking help from a professional mechanic who has experience with OBD-II diagnostics. By following these steps, you should be able to identify and resolve the issue causing the P0652 code

Definition

Common causes

Common misdiagnoses

Troubleshooting steps

1. Check the Vehicle's Battery and Charging System

2. Ensure the battery is fully charged and in good condition

3. Check the alternator and charging system to ensure they are functioning properly

4. Inspect the MIL Bulb

5. Verify that the MIL (check engine light) bulb is not burned out. If it is, replace it and clear the code to see if it returns

6. Examine the Wiring and Connectors

7. Inspect the wiring and connectors related to the MIL circuit for any signs of damage, corrosion, or loose connections

8. Pay special attention to the wiring harness that connects to the Engine Control Module (ECM)

9. Check the Ground Connections

10. Ensure that all ground connections related to the ECM and MIL circuit are secure and free of corrosion

11. Test the MIL Control Circuit

12. Use a multimeter to check the voltage and continuity of the MIL control circuit. Compare your findings with the specifications in the vehicle's service manual

13. If the voltage is low or there is no continuity, trace the circuit to find the fault

14. Inspect the ECM

15. If all other components check out, the issue may lie within the Engine Control Module itself. Check for any software updates or reprogramming that may be needed

16. In some cases, the ECM may need to be replaced if it is determined to be faulty

17. Clear the Code and Test Drive

18. After performing repairs, clear the code using an OBD-II scanner and take the vehicle for a test drive to see if the code returns

19. Consult Technical Service Bulletins (TSBs)

20. Check for any TSBs related to the P0652 code for your specific make and model, as there may be known issues or fixes

21. Seek Professional Help

22. If you are unable to resolve the issue after these steps, consider seeking help from a professional mechanic who has experience with OBD-II diagnostics. By following these steps, you should be able to identify and resolve the issue causing the P0652 code