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Hi All,
I'm wondering if anyone can give me some leads on this issue. 1987 W124 300CE. All the tail lights and number plate lights are non functional. Checked the fuses #3 and #8 and they are fine. Checked the globes, they are fine. There doesn't seem to be any power getting the circuit. I had been messing with removing an after market alarm, but I don't think that has caused the issue. The factory alarm is still fitted, but again, not sure that should affect tail lights? It's got me scratching my head! Any suggestions would be much appreciated. Thx
190E 2.6L 1989, 190E 2.6L 1988, BMW 535dXdrive 2014, BMW 428i 2015
Have you check the ground circuit? Generally the brown ground wires are shunted to the body in the trunk near the tail lights. The connection may be loose or corroded.
Thanks dolucasi, I assume you mean these. I removed the ground and cleaned the ground point and eyelets. No better, but I did a little more troubleshooting. It now appears the tail/parking lamps are the ones not working (rear indicators, brake and reverse lights are working). The standing lamps also don't work, but I assume these are the as the same as the tail lights? Interestingly the headlamp flasher/ high bean also does not work. Not sure if that could be related. If anyone has some ideas it would be much appreciated. Cheers
190E 2.6L 1989, 190E 2.6L 1988, BMW 535dXdrive 2014, BMW 428i 2015
Take a more zoomed out photo of the area. Not sure if that is the taillight ground. That picture looks like the antenna area but I can not tell.
Where are you located? US or Europe? Do you have city lights for park lights?
Also tell us about this aftermarket alarm system you removed. Often (like my W201 car because I wired it) people use the parking lights for feedback when the alarm/keyless entry is activated.
The photo is of the LHS, near the aerial mount. They were the only grounds I found, as I assume all the wiring to the back of the car runs down one side? The parking lights are not working either. The car is a UK import spec. I don't believe the alarm is the cause, as all the wires related to it I carefully unpicked, and where spliced into the original wiring (i.e. MB wires just had their insulation peeled back and the alarm wire spliced in). I made sure to return the wiring back to how it was, and re-insulated all the splices. So why the tail lights, parking function and licence plate lights don't work is a mystery still.
Last edited by Achillies1975; Apr 28, 2025 at 07:04 PM.
190E 2.6L 1989, 190E 2.6L 1988, BMW 535dXdrive 2014, BMW 428i 2015
On the W201's at least the tail lights have separate ground connections and they do not share the antenna motor chassis connection. At least on the right side. Make sure the chassis connection is not corroded.
On the alarm you disconnected make sure you got it all. One of my 201's had an Alpine alarm system clearly installed at the dealership when new. This beast have wires everywhere.
I thought I removed everything and all of a sudden my headlights would come one with no key in the ignition. There was a motion detector under the seat and all the connections to the central locking pump had Bosch relays on them for the alarm. Anyway, after removing the motion detector and all the relays everything went back to normal.
So make sure every alarm element is properly removed.
Thanks for the feedback. I wish my life was so easy that it was just a bad ground . I had already tested the BR ground wire from the rear light plugs to the body. Continuity was all good. And after your suggestions I found the light ground to the body and cleaned it up. No joy!
I'm pretty confidant I got all the alarm wires sorted back to factory. I managed to get a copy of the alarm installation manual and used it to reverse the installation.
It might be worth mentioning again, that the rear indicators and brake lights work, just not the tail lights, parkers, licence plate lights.
190E 2.6L 1989, 190E 2.6L 1988, BMW 535dXdrive 2014, BMW 428i 2015
How about reverse light? If that works it sounds more like the hot circuit of the tail/license plate is not powered up. You will have to trace that circuit all the way back to the source then.
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. I had already tested the BR ground wire from the rear light plugs to the body. Continuity was all good. And after your suggestions I found the light ground to the body and cleaned it up. No joy!
