P0654 – OBD-II DTC

OBD-II DTC P0654 – Malfunction Indicator Lamp (MIL) Control Circuit Malfunction

DTC P0654 meaning

DTC P0654 refers to a malfunction in the Malfunction Indicator Lamp (MIL) control circuit. The MIL is a warning light on the vehicle’s dashboard that indicates a problem with the engine or emissions system. This code indicates that the Engine Control Module (ECM) has detected an issue with the circuit responsible for controlling the MIL, which may prevent it from functioning correctly.

DTC P0654 symptoms

Common symptoms associated with DTC P0654 may include:

• Illuminated Malfunction Indicator Lamp (MIL)
• Possible lack of power or performance issues
• Increased emissions
• Potential failure of emissions tests

DTC P0654 causes

Several factors can lead to the triggering of DTC P0654, including:

• Faulty wiring or connectors in the MIL control circuit
• Defective Engine Control Module (ECM)
• Malfunctioning MIL bulb or LED
• Short circuits or open circuits in the MIL control circuit
• Corrosion or damage in the electrical connections

DTC P0654 seriousness

The seriousness of DTC P0654 can vary. While it may not indicate an immediate threat to vehicle safety, it can lead to:

• Inability to monitor engine performance
• Increased emissions, potentially leading to environmental issues
• Failure to pass emissions testing
• Potential for more severe engine issues if left unaddressed

How to diagnose DTC P0654

To diagnose DTC P0654, follow these steps:

1. Use an OBD-II scanner to confirm the presence of DTC P0654.
2. Inspect the MIL bulb or LED to ensure it is functioning properly.
3. Check the wiring and connectors in the MIL control circuit for damage or corrosion.
4. Test the continuity of the circuit to identify any open or short circuits.
5. Examine the Engine Control Module (ECM) for faults or software issues.

How to fix DTC P0654 step-by-step instructions

To fix DTC P0654, follow these step-by-step instructions:

1. Replace the MIL bulb or LED if it is found to be defective.
2. Repair or replace any damaged wiring or connectors in the MIL control circuit.
3. Ensure all electrical connections are clean and free of corrosion.
4. If the ECM is faulty, consider reprogramming or replacing it.
5. Clear the DTC using an OBD-II scanner and test drive the vehicle to see if the code returns.

How to erase DTC P0654

To erase DTC P0654, follow these steps:

1. Connect an OBD-II scanner to the vehicle’s diagnostic port.
2. Turn on the ignition without starting the engine.
3. Navigate to the “Erase Codes” or “Clear DTCs” option on the scanner.
4. Confirm the action to clear the codes.
5. Disconnect the scanner and start the vehicle to ensure the code does not return.

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