# Check Clutch Switch w/ VAG COM



## 01TornadoWolf (Jun 18, 2009)

long story short i have rev hang in my mkiv and the blue clutch switch is one of the possible causes of this. the switch also tells the cruise control to shut off when the clutch pedal is pressed in. so i set my cc and pressed the clutch in and the engine revs went up aka switch broken.
replaced the switch and still have rev hang and rpm still go up when clutch pedal pressed in w/ cc on.
i read that i could check this switch through vagcom so here's what i did. looking at 'measuring block 066,2 brake switch' (i think) the bits read something like 0001000 with both brake and clutch pedals not pressed. pressing brake pedal gives 0001111 and i would assume pressing clutch pedal would give 1111000 but it does not.
am i looking in the right place on vag com for clutch switch functionality??
thanks!!
using version 409.1 btw if it makes a difference


_Modified by 01TornadoWolf at 10:21 AM 9-22-2009_


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## 01TornadoWolf (Jun 18, 2009)

*Re: Check Clutch Switch w/ VAG COM (01TornadoWolf)*

bump for vagcom help!


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## Uwe (Jan 16, 2000)

*Re: Check Clutch Switch w/ VAG COM (01TornadoWolf)*

The brake switch has two redundant contacts in it. Hence there's two bits, one for each contact. The clutch switch only has one set of contacts in it, hence there's only one bit.
If you want more specific advice, please don't post values that "read something like". Post EXACT data.
-Uwe-


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## 01TornadoWolf (Jun 18, 2009)

*Re: Check Clutch Switch w/ VAG COM (Uwe)*

understood and when i get a chance i will grab screenshots etc.
basically my question was am i looking in the correct place to check if the clutch switch is working or not because i was not seeing the bits change no matter what position the clutch pedal was in.
will update with more specifics when i get the time to rerun.


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## 01TornadoWolf (Jun 18, 2009)

*Re: Check Clutch Switch w/ VAG COM (01TornadoWolf)*

ran vagcom again. group 066,2 is labelled "Brake Position" when neither the clutch nor brake pedal are pressed it reads 00001000, when the brake pedal is pressed it then reads 00001111.
pressing the clutch pedal has no effect on the readings. am i looking in the wrong place to be monitoring the clutch switch (aka clutch vacuum vent valve switch)? or is the 1 that doesnt change (5th digit) supposed to be the clutch switch?


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## 01TornadoWolf (Jun 18, 2009)

*Re: Check Clutch Switch w/ VAG COM (01TornadoWolf)*

bump


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## Uwe (Jan 16, 2000)

*Re: Check Clutch Switch w/ VAG COM (01TornadoWolf)*

The last four bits in field 2 should work like this;
----1xxx - Cruise control system active
----x1xx - Clutch depressed (always 1 in automatic transmission)
----xx1x - Brake depressed (brake pedal switch)
----xxx1 - Brake depressed (brake light switch)
Seems like you might have some sort of wiring issue there?
-Uwe-


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## 01TornadoWolf (Jun 18, 2009)

*Re: Check Clutch Switch w/ VAG COM (Uwe)*


_Quote, originally posted by *Uwe* »_The last four bits in field 2 should work like this;
----1xxx - Cruise control system active
----x1xx - Clutch depressed (always 1 in automatic transmission)
----xx1x - Brake depressed (brake pedal switch)
----xxx1 - Brake depressed (brake light switch)
Seems like you might have some sort of wiring issue there?
-Uwe-

thanks! yea looks like ive got my work cut out for me! fun times.


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## 01TornadoWolf (Jun 18, 2009)

*Re: Check Clutch Switch w/ VAG COM (01TornadoWolf)*

alright so after a lot more 'debugging' i still couldn't find my issue. i figured it had to be a wiring problem so i actually cut the clutch switch wire right at the ECU. this changed nothing and when depressing the brake pedal the ECU still thinks both the brake and clutch pedals are being depressed.
to me this makes absolutely no sense. the clutch bit should not be changing at all anymore since the wire has been cut.
correct me if im wrong but i think the only other option is that there is an issue with my ECU or software (APR)...


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