S-Class brake light switch

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Mon 26 Mar 2007 16:08
S-Class brake light switch - Big Vern
Hi

I was looking at my Dads 98 W140 S-Class. It is an auto and the ABS / ASR light is on. I read the fault codes and found that it is fitted with a Bosch ASR module MB# 018 545 47 32 HW version 46/97 SW version 18/96. Fault code C1200 brake light switch: open circuit / bad contact /plausibility.

Does anybody know where the switch is located?

I had a good shuftie around the footwell and could not seem to get the trim above the footwell off to look at the point where the brake pedal pivots. There is a load of electrical gubbins around the master cyinder and ws wondering if the switch was around there.

Thanks in advance

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Mon 26 Mar 2007 19:46
S-Class brake light switch - elekie&a/c doctor
The brake light switch is located on the pedal box assy behind the dash.Access requires removal of the underdash carpeted trim and also the plastic under panel that covers the pedal mechanism.The switch has a 4 pin connector attached to it and is bayonet fit into the pedal housing.hth
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Tue 27 Mar 2007 09:54
S-Class brake light switch - Big Vern
Thanks for that, I was just wanting to make sure that it was in there before I went to the hastle of taking all the trim off, it just is not as easy as taking the two screws out :o)

Any idea why the brake lights work but this switch seems to annoy the ABS / ASR ?
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Tue 27 Mar 2007 20:28
S-Class brake light switch - elekie&a/c doctor
The brake light switch on these is a double contact device.When the brake is appied 1 set of contacts make a circuit for the lights while at the same time the second set of contacts break a circuit to the abs/asr system.It's usually the latter set that causes the fault ,so the brake lights still work.. The switch is cheap; about £10.hth
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