What's happening? Is it the Awesome haldex unit?

quattrokid

quattrokid

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Ok.... Whats going on...( just had its 40'000 mile service) bought the car in January with 38500 miles on it , now up to 41500 ish) the yellow warning lights first came on dn route home from buying it in Wales.... the lights comes on regardless of speed or driving style...

Brake fluid was changed twice,yesterday, this sensation of the abs kicking in sometimes under hard braking...

scanned again absolutely nothing is bringing up any fault codes at all, he took some logs or whatever it's called and each wheel sensors regulator in the abs unit is spot on as well, wheel alignment was done and very slightly tweaked, the wheel
sensors where all checked and all are in fine fettle, discs and pads don't look that old either...

BUT STILL the yellow abs and traction control lights come on for no apparent reason, came on rn route to my Mums this afternoon.

The only mod it's had is the Awesome haldex ecu has been upgraded for an aftermarket one. No vag com codes for that either, brake pedal does seem to have a fair bit of travel in it before the brakes bite
I'm going to call Awesome tomorrow and ask their techy guys what they think. even with warning lights luninated there are no fault codes and non stored!!!!

Any suggestions please *
 
Do you still have the original haldex ecu? If so it wouldn't hurt to switch them back over and see if that cures it. Having had a few haldex issues in the past I would say its unlikely thats your cause though, I've had a pre charge pump and ecu die at seperate times and all I had was a lack of AWD and serious torque steer lol No lights or any other symptoms. Sounds stupid but are your brake pad sensors intact?
 
the master tech who serviced it, im sure he knows what to look for, i assume the pad sensors are intact, he went over the car with a fine tooth comb, its currently got him stumped. trying another local S3 and see what readings that has in comparison to ours. No i havent got the original haldex ecu, it was changed by the last owner... at an expense of circa 600 quid !!!!

would a pre face lift S3 have the same ecu as a 2001 model?

what difference would it make IF the pad sensor was tits? why would the pedal feel spongey? on our last S3 we nearly went out the window because the brake pedal was sooo sensitive !! this one is about half way down before it starts doing any braking !!
 
quattrokid said:
Ok.... Whats going on...( just had its 40'000 mile service) bought the car in January with 38500 miles on it , now up to 41500 ish) the yellow warning lights first came on dn route home from buying it in Wales.... the lights comes on regardless of speed or driving style...

Brake fluid was changed twice,yesterday, this sensation of the abs kicking in sometimes under hard braking...

scanned again absolutely nothing is bringing up any fault codes at all, he took some logs or whatever it's called and each wheel sensors regulator in the abs unit is spot on as well, wheel alignment was done and very slightly tweaked, the wheel
sensors where all checked and all are in fine fettle, discs and pads don't look that old either...

BUT STILL the yellow abs and traction control lights come on for no apparent reason, came on rn route to my Mums this afternoon.

The only mod it's had is the Awesome haldex ecu has been upgraded for an aftermarket one. No vag com codes for that either, brake pedal does seem to have a fair bit of travel in it before the brakes bite
I'm going to call Awesome tomorrow and ask their techy guys what they think. even with warning lights luninated there are no fault codes and non stored!!!!

Any suggestions please *
Click to expand...

Faulty maf sensor can throw light
 
Check the fuses on top of the battery, check for corrosion and blown fuses.

Pull each one out once at a time, wipe the spades in a rag and put them back in.
 
the MAF sensor? i thought that measured the air temperature and density of the air coming into the engine, IF that was tits then i would have thought it wouldnt run smoothly as the air / fuel mixture would be all over the place, not sure how that would effect the abs and traction control warning lights... BUT i'd be delighted to be enlightened :)

wouldnt a dodgey MAF bring up a fault code?

cheers for your input gents....
 
Maf would not bring up traction control and ABS lights.
Can you turn the traction control (esp) button off?
Is it chewing front tyres up on the inside?
 
quattrokid said:
the MAF sensor? i thought that measured the air temperature and density of the air coming into the engine, IF that was tits then i would have thought it wouldnt run smoothly as the air / fuel mixture would be all over the place, not sure how that would effect the abs and traction control warning lights... BUT i'd be delighted to be enlightened :)

wouldnt a dodgey MAF bring up a fault code?

cheers for your input gents....
Click to expand...

gen.heinz guderian said:
Maf would not bring up traction control and ABS lights.
Can you turn the traction control (esp) button off?
Is it chewing front tyres up on the inside?
Click to expand...

the ECU needs to know the engine load to be able to use ESP correctly... if its blind to load (airflow from the MAF) then it can't control actual load (through the throttle plate)... if MAF is faulty/disconnected, ESP light comes on..

What are you scanning it with? if there are lights on the dash there WILL be a fault code in either the ABS, AWD or Engine modules...

<tuffty/>
 
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