car immobiliser problem

annie123

We have a 20 year old BMW with a scorpion immobiliser fitted.

The back door wasn't shut properly when the car was locked via central locking, opened door whilst other doors are locked, pushed down lock and closed but it popped up again so got key fob, did the blip thing and all doors locked.
Went to use it this morning and now the car won't start and the blip thing does not open the doors.
The blip lights up (have tried a new battery, in case) but doesn't do anything, dashboard lights up as it should, have tried a jump start in case battery problem but nothing.

Scorpion alarm company no longer in business so can't get a manual.
(Neighbour told me this but have just found a web site that is probably them)
How can I reset the immobiliser ?
It now thinks it's been tampered with due to door opening and closing whilst the central locking was on.

Any ideas gratefully received.

mikey72

Without knowing the alarm number, try holding down the fob button for 30s or so. Is there a keypad in the car?

edit - try with each fob button in turn, with the ignition key in each position as well.

annie123

no keypad in car, off to try holding down fob, no buttons on it, just a pressure sensor area.

annie123

Nope, not worked.

esmerobbo

Have you checked the fuse to the alarm unit is ok? It is an after market alarm so everything will be commanded from the alarm unit! Do the ignition lights come on?

annie123

good point hadn't thought of a fuse, but need to find it first!
yep all ignition lights come on as usual, and the radio even though I keep turning it off.

Off to see if I can find alarm unit.

annie123

have come to the conclusion that I have no idea what I'm looking for:o

what would the unit look like? big, small, little black box?

We were given the car by hubby's aunt, they had it fitted, so its going to be around 15/20 years old if that helps.

esmerobbo

What model BMW is it? The power for the alarm will either come direct off the battery or from the fuse box. Most wires are in a loom of many wires wrapped together with tape or cloth. The alarm wire will probably be single wire feed.

It will probably be a black box, try and locate the siren under the bonnet and follow the wires back. It will either be in the engine bay or tucked up under the dash! [usually]

annie123

Its a 325i se and thank you, off to rummage around wires