Flip Key and Electronic Anti-theft Error (C3/C4)

There are two distinct technologies within your flip key: the Remote control (opens the doors) and the Transponder (allows the engine to start).

• The Problem of Control (Gateways): If the car doesn’t lock/unlock with the button, 90% of the time it’s the CR1620 battery (or CR2032 in newer models) that’s over.
  • Careful: If you take too long to change the battery or repeatedly press the buttons away from the car, the key may “waste” the synchronization code.
• The Problem with Anti-theft Devices (Start): If the car won’t start and displays an error message, the problem is the… Transponder. It’s a small chip (it looks like a grain of rice or a small black square) that sits loose inside the casing.
  • Common Cause: If you dropped the key and the casing opened, this chip may have fallen out. Without it, the antenna (coil) around the ignition will not recognize the key and will block the ignition for safety reasons.

How to Sync the Controller (After Changing the Battery): If the remote control doesn’t work after replacing it, try this procedure:

1. Place the key in the ignition and turn on only the panel (position 2).
2. Immediately press and hold the button. to close for 10 seconds.
3. Turn off the ignition and remove the key.
4. Wait 30 seconds without touching anything. The controller should start working again.

Location of Protection (Fuses): If even the spare (simple) key doesn’t start the car and the anti-theft message persists, the problem may be the fuse for the receiver antenna. BSI (Cabin):

• Correct Fuse: Generally the F8 (20A) or the F15 (15A), which power the steering column and the recognition modules.

Golden Tip: Never use low-quality “parallel” keys for the transponder, as they can lose their code due to the heat of the dashboard, leaving you stranded on trips.