Rear tail light no working

[tvr tommy]

My drivers side rear tail light has packed up on the W124 1992 coupe. It's not getting any power. The rest of the light works fine. The plug that goes into the bottom of the bulb mounting board isn't getting any + power the earth is fine. I've read in the Haynes manual that there is a lighting control unit between the light sector switch in the dash board and the rear light cluster. Where is this to be found? Is it the box I've found under the left rear passenger seat?

The light buzzer still works which takes power from the driver rear light fuse so there power getting as far as the fuse box. So that says to me that the dash switch is working fine.

Any help would be great.

 

[Frank O' Phile]

Try reading through this current (no pun intended) thread.

http://www.mbclub.co.uk/forums/showthread.php?t=53892

Seems the boot wiring could be a cause.

 

[Howard]

Shouldn't affect the tail lights as they aren't anything to do with the supply to the boot.

Does the other tail light work ok ?

 

[tvr tommy]

The passenger tail light works fine. It's just the drivers side which has lost power.

 

[Howard]

Is the whole cluster out or just one bulb not receiving power ?

 

[tvr tommy]

It's just the rear tail light thats not getting any power. Fog and indcators work fine.

 

[Howard]

Corrosion ? a break in the metal power distribution grid ?

 

[alibally]

The bulb failure relay that is mounted under the rear cover in the fusebox is connected all the lamp units. Checking for a feed from that unit to the rear light unit will give you a clue whats wrong. You will need a little electrical savvy and a wiring diagram to check it properly. If in any doubt seek help from an mb dealer.