300tdi alarm problems

[hxk494]

Hi all.

I've got a 1996 Tdi 110, have had it on the road for about two years now and in all that time no problems with the factory fitted alarm/immobiliser (green box behind dash and metal box attached to front of battery box) - until 2 days ago when the alarm started sounding in the evening for no apparent reason (wasn't set when this happened), only silenced by disconnecting battery, it didn't respond to fob. Reconnected battery the next day (after charging it for good luck) and all seemed OK, until evening again when alarm started sounding, again disconnected battery and that silenced it. All seemed to be working as usual until the later triggering on the second day.

Any thoughts on where to start looking for a fix for this, or is removal/bypass a better plan? I've read plenty about the "spider" but get the impression this is the immobiliser not the alarm? Also, where is the sounder, can't see anything under the bonnet but may be tucked up tight behind nearside wing - really need to trigger it and listen to find out - would unplugging sounder be a short term fix or just bring more problems - apart from obvious difficulty of finding/accessing it?

Thanks,
Martin.

[theredjerseys]

Hi Martin the the starter circuit.

I had the same problem about 2 .years ago I bypassed the alarm and disconnected the sounder under the wing.I suggest to go online and download a copy of the wiring diagram that covers the immobilizer. You are looking to bypass the fuel solenoid and starter circuits. One bypass needs to be done on the circuits behind the panel in the cab containing the relays.The other  bypass needs to be done in the battery box .Get yourself a multimeter to trace the wires . not a major job should take a morning to do.Make sure cables are soldered for continuity

 

Mal