Broken Trunk-Lid Wiring
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Broken trunk-lid wiring occurs when the harness that carries power to the license plate lights fractures inside its loom, typically at the sharp bend near the trunk hinge. This is a cosmetic fault with no impact on drivability. The break interrupts the electrical feed to one or both license plate lamps, and in some cases can trip fuse F37. Most owners first notice the outage during evening driving or when backing up.
What it feels like
One or both license plate lights stop working. The lamps themselves may be intact and the bulbs good, but no power reaches them. In rare cases, the broken wire causes a short that blows fuse F37, cutting power to related circuits. There is no warning light on the dash for this fault. The trunk lid may flex slightly when opened or closed, and if the wire is partially broken, the light may flicker or intermittently work as the harness moves.
How to confirm it
- Turn on the exterior lights and check both license plate lamps. Note whether one or both are dark.
- Open the trunk and visually inspect the wiring harness where it exits the trunk and bends sharply toward the lid hinge. Look for cracked insulation, pinched conductors, or visibly broken wire strands.
- Gently flex and move the harness back and forth while an assistant watches the license plate lamps. If a light flickers in sync with the movement, the break is confirmed.
- Using a multimeter set to DC voltage, probe the lamp socket terminals with the lights on. If you read 0V at both terminals, the break is upstream; if voltage is present but the lamp is dark, the bulb or socket is faulty instead.