W202 Stop light switch reset?

[doversole]

Hi all, DoverSole here, have another annoying little fix for you - i will bet some of you have done it. Basically, you will be driving along and suddenly realise the brake lights are on permanently? (My W202 has the inboard high level brake light and you can see the reflection in the RVM) Anyway, you drop the drivers underdash trim, locate the stop light switch and remove it (bayonet fitting).

Next, pull out the plunger and press the brake pedal to the floor. Hold it there and re-fit the switch. Finally, ease the pedal up slowly and bingo, you've reset the switch! I've had to do this twice since in the last few months, just monitoring things now as I believe if it happens too often, it's new switch time.

Cheers, DoverSole

 

[bigasotonuk]

Hi,
Never heard of this before, thought it was just a straight forward switch.
But if you have had to do this once I would be replacing it A.S.A.P. as if it goes completely it will leave you stranded as the brake light switch interfaces with a lot of other car systems besides the brake lights.
It is only tenner or so from from MB.

 

[doversole]

Thanks for that, I found it in the Haynes manual as a matter of fact - it says if you can't reset the switch it's time to buy a new one. Conventional wisdom suggests the switch needs to be able to cope with varying degrees of pedal travel as the brakes are constantly readjusting. I agree the stoplight is the first link in the chain and supplies the necessary signals to ESP, BAS, ASR etc.

Still, not a bad get-you-home fix. There's nothing worse than following a car with faulty brake lights!

Dover

 

[television]

Under £10 from a MB dealer

 

[whitenemesis]

Just replace the switch..

I guess you could simple pull the plunger free in an "emergency"....

 

[doversole]

Just to let you all know, it's still working fine - thanks for letting me know how much a new one is although I don't need it yet!

Regards, Dover

 

[doversole]

Spoke too soon! Had to reset it again this evening - I will score a new one this Saturday.

Dover

 

[doversole]

Have the new one here and ready to go in. Many thanks to Ellsy Tanners for bringing it round, let's have that beer sometime, ET.

DoverSole

 

[Ellsy Tanners]

Anytime Dover, glad to be of help. ET