Rear lights dim (one side)

[kap02]

A friend of mine noticed that one of my rear lights was dimmer then the other side on my W204.

Before I start changing bulbs I have done some searching and there seems to be an issue?

Does anyone have further information on this?

 

[Prash87]

Best thing would be to take out bulbs on both sides and check the Voltage and if the dim one should be less power get one at ECP for around £2-3max and you solved the issue =) if both should be the same Voltage try the bulbs in the other ones light and see what happens.

 

[kap02]

Cheers blood

 

[Prash87]

Let us know the outcome

 

[kap02]

Cheers!

 

[kraven]

This is a real common problem with W204's, the connector which connects to the bulb holder corrodes inside the connector. Remove the connector, if you even can as mine was completely corroded and wouldn't come out, and you'll see it's corroded.

You'll need to buy a new rear bulb holder, the black connector and the pins and then take it a local car electronics repair shop to have the cable cut and new pins attached.

When I had it done, parts cost about £15 per side and then £15 labour. The connector has 7 pins each side, but you'll find the ground is the one which has corroded and this usually shorts against the next pin, hence the lights fade. You probably will only need to replace 2 or 3 pins per side.

Although you are seeing this on one side only, you'll find the other side is going as well.

I suspect it's coming from where there are vent holes which allow air from inside the rear wheel arch to escape and water vapour is seeping into the rear light.

You can get it done by a dealer, but they'll charge a fortune.

If you're car is under warranty, then get it down there quick!!

See - http://mbworld.org/forums/c-class-w204/432136-flickering-tail-light-help-please.html

 

[kraven]

Potential recall mentioned in the US - Recall on C300 taillights, true? - MBWorld.org Forums

Bizarrely this also affects BMW E46's - http://www.youtube.com/watch?v=GkQfyxNJLw4

 

[kap02]

This is a real common problem with W204's, the connector which connects to the bulb holder corrodes inside the connector. Remove the connector, if you even can as mine was completely corroded and wouldn't come out, and you'll see it's corroded.

You'll need to buy a new rear bulb holder, the black connector and the pins and then take it a local car electronics repair shop to have the cable cut and new pins attached.

When I had it done, parts cost about £15 per side and then £15 labour. The connector has 7 pins each side, but you'll find the ground is the one which has corroded and this usually shorts against the next pin, hence the lights fade. You probably will only need to replace 2 or 3 pins per side.

Although you are seeing this on one side only, you'll find the other side is going as well.

I suspect it's coming from where there are vent holes which allow air from inside the rear wheel arch to escape and water vapour is seeping into the rear light.

You can get it done by a dealer, but they'll charge a fortune.

If you're car is under warranty, then get it down there quick!!

See - Flickering Tail Light, help please - MBWorld.org Forums

thats a joke!

I might call mercedes benz customer services see what they say.

It is out of warranty.

 

[Image2000uk]

try checking the earth to the rear cluster as a rusty earth would cause a dim bulb

 

[Prash87]

Bizarrely this also affects BMW E46's - E46 Tail Light Recall Procedure - YouTube

Not only E46 (owned one and had the bulb holder replaced) also the E36 Coupe had the issue (had the holder also replaced).

 

[kraven]

thats a joke!

I might call mercedes benz customer services see what they say.

It is out of warranty.

So how corroded was your connector ?

 

[kap02]

So how corroded was your connector ?

Not even had a chance to look at it yet

Ill will update once I do.

 

[kap02]

Sorry for the late reply, as Kraven suggested it was the bulb holder.

I had the whole unit replaced with bulbs, I got SPR Autos to carry out the work. Spot on!

 

[limby]

Resurrecting an old thread here but I have just had this same problem on my w204 (2008). Rear LHS lights, connector earth pin corroded and melted.

There is a single pin used for the return current from the entire light cluster and it's not up to the job. I snipped the old wire off the connector and pulled out the melted pin and connected a new thicker earth wire from the bulb holder board (there is a handy spade terminal on the earth track) and connected it to a bolt on the chassis (there is one in a handy location just next to the lights inside the boot. I did the same on the lights on the other side as a preventative measure.

Cost less than a fiver and very easy to do, a couple of crimp connectors and some wire. If anyone wants details let me know.

 

[Bjm34new]

just noticed this on mine and yep corroded connectors