Strange cruise control problem

Yeah thats right, it's just the signals it sees are different....

 

sounds like a plan, il try that tomorrow. So do you think the one of the brake switches isnt working either?

the lights obviously work but there is a blue and a black switch on the brakes.

 

Yeah if you look in your first video you can see of the two brake switch values only one is going to 1 when you press the brake pedal. The other one is staying at 0.

 

ok so am i going to have to take a 12v ignition feed from somewhere and cut one of the wires to the clutch switch and the non working brake switch?

 

Yes take a fused live feed from a wire near the fusebox. The brake switch you need to change should be connected to pin 20 of the ecu. And again it needs to give the ecu 12v when the pedal isnt pressed and nothing when the pedal is pressed.

 

Cheers for the help mike, il try it tomorrow and let you know how it went

 

I did change the cruise on signal wire, thats deffinatly in a different location on this new ecu. all makes sense now, il get it sorted later today

 

If it doesn't work still you might have to try the other pair of original audi chips mate and see if those work. If they do and the other ones don't I will get you a tuned pair of those sent out.

 

I will let you guys know when i get from the MOT, il mock up a power feed to both and see what happens.

Cheers mike, il try those chips first before i make the changes.

 

Those chips definitely won't work without the changes mate so not really worth trying them.

 

ok, well we will see what happens, fingers crossed, if this works il need to put something into the cruise guide so if anyone gets the same issue with a different ecu they will know what to do.

 

So i guess it also explains why my gear changes are not very smooth at the mo, as the ecu isnt backing off the fuel momentarily when the clutch is dipped.

 

right, after testing the theory, the switches work the opposite way to the way they should, so with the clutch and brake pressed, there is no signal, but when not pressed there is signal to both.

so im guessing the audi switches work in the opposite way too

so based on that i need an audi a4 clutch and 2nd brake switch?

 

having done some more digging, the brake switch for the lights works in the way I want it to, ie push to break. So I have ordered two of these as the Audi clutch switch is silly money. fingers crossed it should now work.

Although I dont understand why the cruise control wont engage as without the presence of a signal the ecu should assume the pedals are not pressed.

 

All sorted, working fine. Cruise now works fine, no fault codes, all good. Cruise on switch needed to be rewired in order to match the reverse wiring for the audi ecu.

Just need to fit a brake and clutch switch. So at the mo the only way to cancle is to shut off the cruise control.

Cheers john and mike! Legends

 

So...to clear this up, the audi cruise control switches work differently to the vw ones or is this a 8/16 bit ecu issue??

 

I dont if its an audi or a 16bit issue, im guessing probebly a 16bit change.

 

Its an Audi 16 bit issue, I'm 95% sure that changing to a vw 16 bit shouldnt have these problems. But the audi ones come up more often at a better price.