Water Infiltration and Short Circuit in the Trunk Lock (Citroën C3)

Water entering the trunk of the C3 is a chronic problem, usually caused by the drying out of the seals on the taillights or the rubber trim on the trunk lid. When water seeps into the metal body, it can reach the wiring harness and the trunk lock motor, causing a short circuit.

• Focused Model: Citroën C3 (First and Second Generation).
• Location of Protection: The fuse that protects the electric locking system (including the trunk lock) is located in BSI (Integrated Services Box)inside the cabin, below the dashboard.
• Correct Fuse: It’s the fuse. F14, with amperage of 15A.

Consequences of Infiltration:

1. Fuse blown: If water gets into the electric lock connector, it will cause a short circuit that will blow the fuse. F14 (15A). If this happens, you won’t be able to open the trunk using either the external button or the remote.
2. Lantern Oxidation: Water can also accumulate inside the taillights, burning out the bulbs and oxidizing the printed circuit board (socket).

Solution: Before replacing the fuse, it is vital to dry the lock connector with contact cleaner and seal the taillights with neutral silicone or replace the rubber gaskets. Otherwise, the fuse will blow again in the first rain.