Stove

I installed a new stereo in my 2004 A4 1.8T last night, and this morning the car wouldn't start. It would turn over, but never fire up. Everything else works (including the new stereo). My initial thought was that it was a low battery, but the battery is fine. I next checked all of the fuses in the fuse box at the driver side end of the dash, and none of the fuses were blown. I quickly called two shops, and they both said it was either "an electrical problem or a fuel pump issue", but I can hear what I think is my fuel pump working, and since I installed the stereo last night, I assume it has to be "an electrical issue."

Any help would be appreciated, and I am not the greatest with cars so please make sure any suggestions are detailed enough to allow me to try it.

lyleswk

I suspect you activated something called the immobilizer. I have read on other forums of guys swapping radios and in the middle, turning the key on to check something, roll windows down, etc. This sets the immobilizer. Do you have the word "safe" where the mileage is?

Stove

No where does it say "safe". The miles show up as normal. Everything on the dash seems normal. I also tried removing the new stereo and installing the factory radio, and still nothing.

lyleswk

I'll go read my manual this weekend to see if the "safe" thing is correct. Are you sure the battery is strong enough?

Stove

Yes, the battery is fine. I even had AAA to give me a jump just in case, and the same thing happened. It will crank strongly for as long as I turn the ignition... it will just never start up.

1.8tb6a4

yeah u def tripped yur immobilizer....try disconnecting your battery for ten min...then reconnect...if doesnt work ur going to have to get your ecu reset

Stove

I disconnected the batter and then reconnected it hours later. Still the same problem. Reading through the forums it seems as though disconnecting the battery resets the ecu. Is there another way to reset it?

lyleswk

Got busy with other activities this weekend. 3 teenage boys , sports , one breaking up with a grilfriend , information session on Rice University , 60 year old home projects . Anyway did not read my manual, but I have exceeded my knowledge. I will just watch and learn. I will say I doubt that it is something mechanical like a fuel pump. Too coincidental, but I could be wrong.

Stove

It ended up locking up my ECU, which needed to be reset. I tried resetting it at home by disconnecting the battery for a couple of hours and then stepping on the brakes to "drain" the system. But that didn't work. The shop I took it to ended up resetting the ECU and everything is back to normal.

lyleswk

Shop meaning dealer? Did you ask any details of what they used? A laptop? VAGCOM tool?

Be good to educate us folks on the forum.