3rd brake light warning but light is working

[Gh3382]

ON my 2010 ML W164 I have been getting intermittant warnings messages regarding 3rd brake light but when I check it the light is working as it should .

I am tempted to check the rear SAM for any water ingress.

Any suggestions as to cure this or confirmation that I should check the SAM appreciated.

GH3382

 

[GP801]

The light is probably on its way out. We had this on and off for a few months on our SLK until eventually it gave up. It can be a DIY fix but they vary. On our W209 it was pretty easy but the SLK was beyond me. A new light from an MB dealer cost less than many on a well known auction site.

 

[Gh3382]

GP801

Thanks for the reply.

I am going to check the contacts then if no joy a new light will be fitted.

GH3382

 

[Gh3382]

UPDATE

I replaced the light. Bit of a bind to get out but there are utube videos on it.

Cost was £83 inc VAT and P&P off fleebay from a Mercedes dealer who had quoted me £97 + vat on the phone.

When taken out all the interior of tailgate frame was wet so I dried it out with a hair dryer .

When I fitted the light I put a thick bead of silicone around the light opening in the tailgate cleaning off any surplus with a wet rag whilst still wet.

I am pretty sure using a jet wash has foorced water into the light so hopefull a good silicone seal will stop that.

Thanks for the help given.

GH3382.

 

[Brown2]

ON my 2010 ML W164 I have been getting intermittant warnings messages regarding 3rd brake light but when I check it the light is working as it should .

I am tempted to check the rear SAM for any water ingress.

Any suggestions as to cure this or confirmation that I should check the SAM appreciated.

GH3382

Hi thanks for your quick reply that's exactly what I'm getting with the intermittent warning i.e. 3rd brake light failure I will check if the light is actually working sorry for being a bit thick what do you mean by SAM