Yr 2000 Audi TT 225BHP Starting Problem

[roybailey]

I have trawled this forum to see if anyone else has had the problem that I'm about to desribe but can't find the answer, so here goes:

I have a fully charged battery on my Yr 2000 Audi TT 225BHP, I am able to 'bump' start (down a hill) the car with no problem whatsoever but the bl00dy thing won't start at the key (not even turning over), when I do get it 'bump' started I get 14volts at the battery terminals. I've measured voltage across the battery and to the engine (all reading 12.5 volts). I'm still thinking engine earth strap.....?? Anyone thinking anything else????

Happy Motoring

Regards

Roy

[sr-performance]

Hi roy, have you checked the wiring to starter motor? I had this with a customers car recently and the thin red wire had come off starter motor so would not start off key..

[roybailey]

Thanks for your reply, much appreciated. I looked at the wiring and tried something else this morning to see if this was the problem, I tried turning the ignition key straight from off to start and the starter gave a little turn on each attempt, so it's probably not the red starter solenoid wire?
When I get home from work this evening I'll check the bigger cables (either from battery to engine or from battery to starter) as I still reckon this may be the problem??? Any other suggestions Please keep them coming......

Regards

Roy

[sr-performance]

Hi Roy, might be worth having your starter checked as well then, just in case it's sticking internally...

[roybailey]

Ok, car now starts fine, here is what the problem was:

Turned ignition key, nothing happened, not even a click.
Battery checked and found to be fully charged and in good condition, replaced battery, no change.
Ran a diagnostics on every possible controller I could (using my evaluation copy of VAG-COM and e bay bought lead), nothing brough up (was paying especial attention to immobiliser in case it was that), nothing pertinent found anywhere.
Took battery and battery tray off just so that I could get to the positive and negative battery cable ends and the starter and solenoid.
Cleaned all of the cable ends and terminal points, put everything back together.
Still wouldn't start so (don't know why) I thought I'd try turning the ignition key straight through from off to start (without pressing immobiliser keyfob button) and the starter gave a turn or two each time I did it, at this point I was completelly confused by what I had (and hadn't) found and was running out of options so went for a cup of tea!

and here was the cure:

I thought I'd exhausted every possible avenue available to me and was about to throw the towel in when I thought I'd try one last thing before taking it down to the local Audi garage.........

I tried the spare key and immobiliser fob....and it works fine!!!! it was the bl00dy key fob all along!!!

I'm posting this here for two reasons. 1) to admit my own stupidity AND 2) to save anyone else a headache and a few hours of labour

[sr-performance]

Ha Ha , nice ending mate, and hopefully you haven't pulled all your hair out!!!!

[shark_90]

Sorry, but it's not the immobiliser. When the immobiliser cuts in it will allow the car to start and run for a second and then cut out. On top of that, the immobiliser light will be flashing.

I'm glad you got the problem sorted but I'm sure (unless there's a flashing light and unless it starts and then dies) that it's not your immobiliser.

[roybailey]

No, it's even more simple than that, it is the battery in my immobiliser key fob! I changed it today and it now works fine, what a donut I am.......

Doh Doh Doh

Regards

Roy

[sr-performance]

Another cheap result!!!

[shark_90]

Sorry to urinate on your chips again.. But the battery is only for the central locking, not for the immobiliser. The immobiliser chip is powered up by the reader coil on your ignition barrel.

Unless the car starts and dies with the yellow car/key light flashing, it's really not your immobiliser.