Passenger side Brake Light will not work

[Rodger K]

Hello I need Help. I have a 98 e320 awhile ago the warning light on the dash came on telling me there was a "Lamp Failure".So I check all lights every light was working fine. The next day everything was back to normal. This happend a couple more times. Then one day it came on again. I checked the lights and found out the Passenger side Bulb was bad. So I changed the lamp and it still has the "Lamp Failure" on dash. And the Brake light on the Passenger side does'nt work but the running light does. I've tried switching the lights from Passengers side to Drivers side It works so I know its not the bulb, Drivers side works fine. I've been told it could be a relay but I thought there is only one for both tail lights. Also I checked the fuses and they look fine. So can anyone give me some ideas what could cause this problem. Thanks Rodger K

 

[jberks]

daft question but have you checked the condition of the contacts in the bulb holder? I had a period where the warning light kept coming on but when I got out to check, the bulbs appeared ok. Cleaned up the contacts with wire wool and bent them back up to make a stronger contact and its been fine since - plus the running and stop lights were suddenly a lot brighter too. The contacts were a bit tarnished but looked ok but clearly they weren't.

 

[Mark Little]

Had a similar problem in my 97 e230. I replaced the whole rear light fitting. There was a bad connection between the bulb holder and the light fitting causing the fitting to melt.

 

[television]

Normally on the lamp failure circuit it only shows front and rear lamps, if you have a brake lamp failure then the warning lamp comes on and stays on once you have pushed the brake.

Malcolm

 

[Rodger K]

Thats right when I put my foot on the brake the warning light comes on. It stays on untill I push the return button on the dash panel, It still shows the two block warning on the upper right hand corner of panel. Mark from Ireland gave me something to think about. I had noticed when taking out the bulb socket it seems like the hole in the brake light fitting was harder to put back in then the left hand side. Its almost like the hole is not round anymore. Thakns for everyones help! Im sure I will something will work out

 

[Rodger K]

Hey Mark, I will look into that. It did seem the bulb socket was harder to put back in the light. it is almost like the hole is not round anymore. The left hand light the bulb socket installs and removes with no problems. Thanks for you help

 

[jberks]

Are you sure you have the right bulb then?
MB bulbs are unusual as the pins are not parrallel but off-set.
If you just ask a parts place for a stop-tail bulb they will give you the wrong one and it will be difficult to fit.

 

[television]

Are you sure you have the right bulb then?
MB bulbs are unusual as the pins are not parrallel but off-set.
If you just ask a parts place for a stop-tail bulb they will give you the wrong one and it will be difficult to fit.

All stop and tail lamp bulbs (twin filiment) have offset pins so you cant put them in the wrong way round. All petrol station's keep them. The two types are

Tail/fog = 21/4W
Tail/stop=21/5W

Malcolm

 

[Rodger K]

I do have the right bulb (twinn filiment) Last night I look at the difference between the left & right assembly. The tail lights have a metal bracket around the back of the light where all of the bulbs twist in. The Drivers side bracket it flat and straight all the way across. But the passenger side bracket seems to have melted down on the inside corner just a bit so the metal bracket is not flat anymore and thats why the pink plastic bulb holder seems to be tight. So im still looking at that as the problem. Once again Thanks for everyones help

 

[mlc]

I have had the same problem with the brake lights on our SLK. both lights have failed over the last year, both in the same way. The contact between bulb holder and light fitting appears to burn a little and get hot which then distorts the light fitting (making it a stiff fitting as described). The only solution I could manage was a complete replacement.

I was totally unimpressed when the second side failed. I can only imagine that MrsC sits with the foot brake on more than MB would expect, have MB not heard of the rush hour!

The good news is that replacement solves the problem.

Mark.

 

[malcolm E53 AMG]

If it is distortion swopping the light units to check would eliminate that problem. Might be worth tracing the lighting wiring back to the junction box and making sure all is well with the pinned connector. If all is well there a circuit tester would prove the the wiring is OK.

After these checks and the others posted above are done it will probably mean taking professional advice.

Hope this helps!