funkadelic

what were the symptoms? My check engine light came on today and this was what I pulled up.

what i'm currently experiencing: engine RPMs stay where they are at for about two seconds before going back down when I fully disengage the clutch...I would assume that a bad clutch pedal switch would causing something like this to happen?

dscottjr

dtc is sending it into rough road mode like pulling the abs fuse or something. I noticed mine cause the CC stopped working and i thought i'd trashed another cc module.

look under the clutch pedal and adjust the plunger to be all the way out when the clutch is out and 'plunged' when the clutch is in. I did that, cleared the code, and it never returned.

good luck.

MachtigAvant (v3.0)

the dealer to swap it out. Damn thing would come on within 180 miles every time I cleared the code. Like dscottjr said, it's a white plunger switch that's under the kneewell. My best bet would be to take it in to the dealer and have them see it. They'll probably clear it and say "no more problem." Tell them you'll bring it in immediately the next time it goes off and it should happen some time within the next week.

'Bahn Burner

<ul><li><a href="https://forums.audiworld.com/s4/msgs/1386550.phtml">click for the post</a></li></ul>

funkadelic

thanks guys...bentley is in hand and going to surgery now..

funkadelic

ends up the clutch pedal switch was disengaged (retracted), telling the ECU that the clutch pedal was depressed when it was not. I guess the tech must have adjusted the switch for some reason the other day while adjusting my clutch pedal and may have forgotten to readjust

per the Bentley manual, the function of the Clutch Pedal Position switch (aka Clutch Vacuum Vent Valve Switch):

<i>This signal is used to avoid RPM over-oscillation and load change impacts when changing gears and is also used for the cruise control system.</i>

This would explain the driveability issues I had...the ECU thought the clutch was disengaged all the time while i was driving around (hence the "17947 - Clutch Pedal Switch (F36): Implausible Signal" DTC)

pre-adjustment: the switch is disengaged in this pic (on the left...the right is the brake switch). this is with the clutch pedal fully out
<img src="http://www.funkadelic.org/albums/clutch_pedal_position_switch_adjustment/aab.jpg" border="1">

measuring block 066: It should say "1000" in the 2nd field from the left since my clutch is fully engaged (pedal out), but says "1100" since the pedal switch is not engaged. Note the field name is erroneously labeled "Brake Position"
<img src="http://www.funkadelic.org/albums/clutch_pedal_position_switch_adjustment/aaj.gif">


post-adjustment: the switch is now fully engaged (as it should be) when the pedal is out
<img src="http://www.funkadelic.org/albums/clutch_pedal_position_switch_adjustment/aaf.jpg" border="1">

measuring block 066 properly reports the clutch is engaged/pedal up
<img src="http://www.funkadelic.org/albums/clutch_pedal_position_switch_adjustment/aai.gif"><ul><li><a href="http://www.funkadelic.org/gallery/clutch_pedal_position_switch_adjustment">http://www.funkadelic.org/gallery/clutch_pedal_position_switch_adjustment</a</li></ul>

lawdogg

Bump from the dead. I have a 2001 allroad 2.7T 6spd and it is throwing code P0704 - Implausible Signal from clutch switch (F36).

I checked underneath and the switch it physically OK - compressed when the pedal is out, and extended when the pedal is in.

I did not check the boolean of block 066, but I did go ahead and order a new switch ($20) from genuinevwuaudiparts.com.

Ever since the MIL came on, I've been having strange driveability issues with engine RPMs and clutch engagement. Hopefully replacing this switch eliminates the symptoms.

Anyway great thread, thank you for the great pictures.

//Ryan

Lucky736

Lawdogg what clutch engagement issues did you have with this, if you don't mind me asking.

lawdogg

It was weird. The clutch felt like it had 7 engagement points. The engine would not rev with the clutch depressed - like, rev match downshifting was impossible. It would bog & jerk almost every time I started to move from a start. With the sensor replaced, went back to normal.