So i just bought a 2004 A4 from a local Auction the other day and just my luck it wouldnt start. The car has been sitting for over a year and the battery was shot. Did a load test and it only had two volts. So i bought a new one installed it and still wouldnt start. everything else works like lights, radio ect. but when u turn the ignition it wont turn over. By doing some reading in this forum i do belive it has to with the immobilizer. the reason i this is because none of the key functions work and yes i did change the battery to a brand new one. any info would be great and when i bought it it only came with one key the one with the lock,unlock,trunk and panic woulod really like to get it running so i can drive this thing. also any info on the 3.0 pros and cons would be great thanks

 

Does the remote on the key fob open the door locks, sound the alarm etc. I don't know how to reprogram if the immobilizer has been functioned, but reprogramming the keyfob to operate the locks etc is in the owners manual.

 

sounds like immobilizer issue if the keys are not working at all. You will need to go to the dealer and have them program them.

 

keyfobs do not work just the actual key works. alarm does set if i put the key in turn and hold it then it sets

 

the key is cut to open the door correct? So it has to do with the immobilizer.

The keys most likely need to be programed with the car. I dont want to say that is the issue because it doesnt make sense to me why the car would be sold to you with keys that dont start the car. How did they move it around at the auction place?

 

If it is the Immobilizer, the light for it will be flashing when you turn the ignition to the On position. If it is active, then the ECU or cluster has been swapped, and you'll need to have the dealer fix it, get a tuner to delete the Immo, or learn to do it yourself (not simple, and you'll need some electronic tools).