What is MID 121:
MID 121 refers to an issue with the Fuel Injector Control Module (FICM), affecting fuel injection timing and fuel efficiency. The ECM detects an abnormal signal from the FICM, which can cause poor fuel delivery, misfires, and performance issues.
Why This Happens:
- Faulty Fuel Injector Control Module (FICM).
- Shorted or damaged wiring in the FICM circuit.
- Loose or corroded connectors.
- Power supply issues affecting the FICM.
- ECM failure to interpret the FICM data correctly.
How to Fix It:
- Inspect the FICM for visible damage or malfunction.
- Test the FICM’s voltage to ensure it’s operating within specifications.
- Check wiring and connectors for visible damage, corrosion, or loose connections.
- Replace the faulty FICM if necessary.
- Ensure proper power supply to the FICM and ECM communication.
How to Avoid It Before It Happens:
- Regularly inspect the FICM and wiring for wear or damage.
- Keep connectors clean and free from corrosion.
- Perform routine diagnostic checks to monitor FICM performance.
- Ensure stable power supply to the FICM and ECM communication.
- Clue’s Fuel Management services monitor injector control systems and prevent issues before they affect fuel injection.
