Light bulb? C'mon...
The error message: “Check the left plate light” comes up.
Bulb removed, the line inside looks OK. Desk test with the spare battery, it is OK, lights up bright.
So, it must be the fuse; I look up the fuse chart, electronic fuse. Then must be a bad/loose/dirty connection, I thought it was unlikely the left and right lights have separate electronic controls.
Trunk lid lining removed, harness disconnected, prongs cleaned, reconnected a couple of times. Lights switched on, voila, the bulb works perfect.
Next day all the same again, back to square one. A bit disheartened I check the connections again, test, the bulb, all perfect.
Discovery: when I close the trunk the bulb goes off!! What the…
I open the trunk fully to up-right position, light works. Slowly push the lid down, at about 60 degree tilt the light begins flickering than goes dark. Experiment repeated many times, always the same. By the way, this is the angle, where the remotely opened lid stops.
So, here are the questions to you: What the plate light has to do with the closing angle? Where shall I look for a malfunctioning connection?
The project is in progress.
You are right, it must be a wire sheared or halfway broke. I located the trouble, it is inside a flat box where the trunk wire bundle retracts when the lid closes.
The box is under the top panel of the trunk. I still need to figure out how to open its cover (which is actually the bottom of the box). I could not find a reference in my MB Service Manual.
Thanks again
All I could do to figure out that the hot wire is broke (unfortunately) the ground is not, so now the left light is feed directly by a piece of wire from the right light.
This would not eliminate the malfunction message, but at least I have light at both sides.





