Alarm starts when doors are locked

When I lock the doors from the outside the alarm will sound until the doors are unlocked. Locking once again will produce a normal single beep. This happens when locking with the remote fob or using the key in the door. The second key produces the same results. On occasion, the locking process will function normally but this is the exception. No other electrical faults are noticeable.

All was well until recently. The normally used key went dead. I changed the battery but still did not function. The second key was put into play and produced the alarm trick. Off to the dealer for a key reprogram of the original key. Now both exhibit the same alarm upon locking. the dealer says that there was a fault code for a shorted horn and wants to replace it. The horn beeps (or peeps) quite nicely and always had so I think it is not the problem.

Any ideas?

Thanks

Hi there,

You would need to get your car on to Vag-Com or even try and get a copy of the fault code read out from the dealer.
It is likely a wiring fault is causing it whether it be external or internal to a control module, but other than that I am stumped!
I tend to agree with you though, the horn shorting shouldn't cause your alarm to go off, unless this is a security feature that if someone try to disconnect the horn then the alarm goes off as that would be the first thing you would want to silence if you were trying to break into the car.

Probably best check the horn connections to make sure they aren't loose or corroded.

sorry for the rambling, just typing as I think :D

Paul :biglaugh:

Thanks for the reply. I'll check the horn connections and inspect the area.

I noticed one additional detail. When the alarm sounds as a result of locking the doors, the side lamps do not flash. When I intentionally set off the alarm the lamps do flash as expected.

This indeed is starting to feel like the car is sending a message that the alarm system is not right.