brake switch again, is this possible??

[chlubb]

I replaced the brake switch 2 months ago. now my brake lights are stuck in the on position. I removed and checked the switch and it appears fine but once the top plug is connected, all 3 lights go on and stay on.
Are these switches junk or have there been other secondary causes to make them fail?

Thanks,
Chris

[mbdoc]

Did you use an OE part or a "Hella" aftermarket cheap part?

[chlubb]

OE MB part, just as Phil has on Fastlane.

[mbdoc]

Make sure! Hella brand have issues!

[chlubb]

who has hella and who doesnt? do the dealers sell hella?
thats where i bought mine last time, it has no brand designation on it.

[mbdoc]

Dealers sell OE parts. If you got it from the dealer you got the correct part.
Did you install it correctly by pre-loading the plunger an extra 1.5mm?

Many aftermarket parts co's will sell "Hella" brand as the OE brand isn't available in the aftermarket.

[chlubb]

MB,
I held in the plunger as I let the brake pedal out but in what way would I need to preload it?

[mbdoc]

MB issued this bulletin & suggests you set the switch 1.5MM deeper.

[chlubb]

the tappet is spring loaded, will it really set itself any different once you remove the spacer? it should just extend all the way out again.

[mbdoc]

It's not the position of the pin you are setting BUT the position of the switch itself.