S4 AAN cutting out while driving

[bluequattro]

Faulty thermal fuses
Mine did it to me on a dual carriageway, in rush hour, in the dark, 2 days before Xmas, on the wrong side of a bend
Ended up with police out and a tow off the road
By the time got to the recovery yard the fuses had cooled and car started
It did it twice more when I tested it
Changed the fuses and it never did it again as far as I know (sold car at end of winter)
That is of course unless it was you that ended up with the car!

[Nace20]

i dont have to wait, i restart the car while it is still moving, and it's fine

sometimes for one minute, sometimes for 20km

today it did it twice in 3-5 km, and it was ok for next 15km,

i hate this faults when it doesnt die and stays dead

[Nace20]

only one fault, to high lambda
i have erased it i look if tomorow is perhaps back

today was running fine :S

[S2central.net]

That is coincidence most likely. Like Mr Schw****negger - your cutout will be back !

[newsh]

aftermarket alarm immob wiring problem?

[Nace20]

no aftermarket alarm, all original, and it 1992 year so no factory immo also

for me it is strange that it all ok, as soon i start it again
it starts and runs like nothing has happened

[Nace20]

That is coincidence most likely. Like Mr Schw****negger - your cutout will be back !

that is what i am afraid, it is a little bit scary to drive just waiting when it will do it again

[UrS4boy]

have you solved this problem, i am having almost same problem, have changed fuel pump relay on sunday, and today i got again two cut outs.
iI have used one used relay, i dont believe that it has same fault, but i have noticed, that after 20 min of driving the relay is a little bit warm, is that normal? i will also check for fault tomorow

Could be any manner of things, e.g. bad wiring to ECU, bad grounds for ECU and/or bad ignition switch.

Missing and hesitation fault finding: http://forums.quattroworld.com/s4s6/msgs/22611.phtml

AAN (and ABY and ADU) won't start solutions info:

http://forums.quattroworld.com/s4s6/msgs/210191.phtml

C4 UrS ignition switch replacement info:

http://12v.org/urs/ReplacingTheIgnitionSwitch.pdf

And BTW, a warm J17 FP relay would be normal, it has current going through electrical wiring coils all the time the ignition is on and the engine is spinning at more than 13 RPM = resistance = heat