Noticed while driving behind the ML which was driven by my wife. None of the lights from both taillights, including the cat eye, weren't working.
Parked the car, locked doors and opened them and only the yellow turning signal lights were working.
Got back home later, went to the garage were the car is parked and the taillights, side markers lit up when unlocking the doors from the remote as they normally do.
Still the brake lights won't work when pressing the brake pedal while parked.
Checked fuse 15 and it was blown.
Changed it, pressed the brake pedal and it blew again.
I put in a 20A and pressed the brake light again, the 20 A fuse blew as well.
Replaced with another 10 A fuse and same thing happened.
I think I can hear the relay clicking when pressing the pedal.
There are no dashboard warning lights coming on and my mini scanner shows 0 codes.
Back in the summer I got rear ended and the left taillight cracked and had to be changed
The body shop changed it but as it turns out it is an aftermarket. Couldn't tell until now when I took it apart. It might be just one connector pin which I see it's bent or it could be the entire light bulb fixture. I will check out the continuity.
However, I think I will get an oem anyway as it costs only $130 from parts.com.
After completely disconnecting the left tail light assembly the rest of the brake lights work now and the fuse no longer pops.
So did it turn out to be a short somewhere in the left tail light assembly? I just had both of my brake lights stop working (even though the top light above the rear window is still functioning when I hit the brake pedal). I am trying to figure out whats wrong. My fuse #15 has not blown and at least the right brake light bulb filament is still intact... Maybe I should remove my entire assembly as well.
Yes. I was checking the bulb fixture and the center contact on of the upper bulb is shorting to ground or at least it's floating because the continuity meter jumps up and down. So the fixture is bad quality.The bent pin on the connector is corresponding with the upper bulb center contact. I just removed the bulb fixture itself and placed the assembly back in place temporarily until I get a new light-bulb fixture which is actually only $13 plus S&H. Hopefully the OEM one which I am buying fits the existing aftermarket lens assembly. Easy fix in my case.
However, in your case, I would try to hear if the relay associated with the brake lights is clicking when you press the brake pedal. You can hear it if the car is in a garage or a quiet place. There are also other ways of checking if the relay is good or if the power gets to the fuse, methods described in this forum if you do a quick search. Sorry, forgot which relay is that but it is also marked on the back of the fuse box cover. But if the center brake light is working as you say, than everything should be fine up to the fuse box, including the fuse box.
I might be wrong but it could be that both bulbs are gone. Even if the filament is there it doesn't mean the bulb is good. I did a quick check of all the bulbs by unplugging the yellow bulb and plugging the other 3 bulbs one by one to see if they come on. just lock and unlock the doors for it to come on.
Thanks, I will check both of those things. Another piece of this puzzle is that I have a trailer wiring harness connected and sticking out by my rear bumper. Could moisture getting into that plug have affected my brake light system?
Thanks! Scott
03' ML500
111,040 mi
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