Clutch Pedal Switch for Engine Start (F194) Fault

[Steve Q]

15 hours ago, evopilot said:

So an update.

Last week after a few weeks of searching i was able to source some genuine VAG diagnostics cables to work with ODIS

I picked up VAG 1598/42 and VAG 1598/39

This then allowed me today to check the signals being received by the ECU which narrowed it down to a fault on wire/pin 44 on the 94 pin side of the ecu, the ECU was seeing voltage permanently but this should have dropped to a earthed signal once the clutch was pressed in.

The culprit wire came out of the master cylinder on pin 3 then split into two parts.... one length went into the convenience module in the boot and the second branched off and went into the ecu at pin 44 as i mentioned above.

Pin pointing that the convenience module was getting the correct signal i was able to narrow down that the trouble was after the cable splits and went to the ecu.

I ran a fresh length of cable myself from the split to the ecu pin 44 and BINGO she fired up, gave the car the once over on ODIS and the error was fully gone.

Nearly six months of the car sitting up in my garage and shes back on the road

So glad you got sorted in the end 🙂

[evopilot]

2 hours ago, Steve Q said:

So glad you got sorted in the end 🙂

i hope that someday somebody on the internet reads this thread and can hopefully use3 my information to not spend so long trying to source the cause of the problem 😄

[Stevey Y]

18 hours ago, evopilot said:

So an update.

Last week after a few weeks of searching i was able to source some genuine VAG diagnostics cables to work with ODIS

I picked up VAG 1598/42 and VAG 1598/39

This then allowed me today to check the signals being received by the ECU which narrowed it down to a fault on wire/pin 44 on the 94 pin side of the ecu, the ECU was seeing voltage permanently but this should have dropped to a earthed signal once the clutch was pressed in.

The culprit wire came out of the master cylinder on pin 3 then split into two parts.... one length went into the convenience module in the boot and the second branched off and went into the ecu at pin 44 as i mentioned above.

Pin pointing that the convenience module was getting the correct signal i was able to narrow down that the trouble was after the cable splits and went to the ecu.

I ran a fresh length of cable myself from the split to the ecu pin 44 and BINGO she fired up, gave the car the once over on ODIS and the error was fully gone.

Nearly six months of the car sitting up in my garage and shes back on the road

Hi it appears the method you used was breathtakingly simple once you had the right kit which looks awesome in the pictures, well done with running in the fresh wire, I must admit the transcript of this problem will lead a lot of people to the solution for the same problem, top marks for persistence and is it to nosey a question to ask how much the shiny kit was.

Steve.

[evopilot]

2 hours ago, Stevey Y said:

Hi it appears the method you used was breathtakingly simple once you had the right kit which looks awesome in the pictures, well done with running in the fresh wire, I must admit the transcript of this problem will lead a lot of people to the solution for the same problem, top marks for persistence and is it to nosey a question to ask how much the shiny kit was.

Steve.

Not at all ask away 😄

ODIS itself and cable 5054 (older cable not the new shiny ones availbile) was about €400/£340 including the laptop

The VAG test cables retail at €1300/£1100 each

The VAG ecu pin out test box i am unsure of the retail but can be gotten on eBay for £100

I was able to source them in the end for €250/£210 all in second hand

GPB prices are approximate for context

My other costs to get to the fix separately were the multiple Master cylinders, a T30 relay and a second hand BCM ecu, by doing it my way in the end i saved an expensive trip to Audi. In hindsight i also saved the cost of a new engine loom already priced at a whopping €2029/£1650 including vat and whatever labor would have been to get to that point

[Steve Q]

5 hours ago, evopilot said:

i hope that someday somebody on the internet reads this thread and can hopefully use3 my information to not spend so long trying to source the cause of the problem 😄

I sure it'll come in useful for multiple people! 

[Stevey Y]

12 hours ago, evopilot said:

Not at all ask away 😄

ODIS itself and cable 5054 (older cable not the new shiny ones availbile) was about €400/£340 including the laptop

The VAG test cables retail at €1300/£1100 each

The VAG ecu pin out test box i am unsure of the retail but can be gotten on eBay for £100

I was able to source them in the end for €250/£210 all in second hand

GPB prices are approximate for context

My other costs to get to the fix separately were the multiple Master cylinders, a T30 relay and a second hand BCM ecu, by doing it my way in the end i saved an expensive trip to Audi. In hindsight i also saved the cost of a new engine loom already priced at a whopping €2029/£1650 including vat and whatever labor would have been to get to that point

Hi thank you for the resume, that is a proper piece of kit that is probably about all you will ever need, rough estimate from my parts system plus labour at around five grand the multiple cylinders from them would be six hundred, all in all a well earned result which for the outlay has already paid for itself.

Steve.

[Salimshk]

Mate you're a life saver. First Audi ever and I have exactly the same issue. On the entire interweb you are the only one that has gone through the same and posted the solution. Thank you! 

I'm.a bmw guy so only have Carly but its showing up errors on the clutch pedal swtich, ABS and comfort access. Receipts show that someone had replaced the mastercylinder last year. 

 

Now time for the dumb question. Where exactly do I find the ECU and the broken cable you refer to? 

[evopilot]

if you open the bonnet there is a large black plastic panel nearest the windscreen the covers from the windscreen to the bulkhead, you will need to remove this.

When this is removed you will see the ECU and the back of the clutch master cylinder too in the same area (drivers side)