I have a 2001 Omega 2.2DTI CDX Estate. Ever since I got the car, the alarm has been silent. Only the indicators flash when the alarm is activated. While thats annoying, its not the end of the world.
Recently however, I noticed most of time when I returned to the car after short periods the hazard lights were flashing. While ultimately I figured out the fault for myself, I wouldn't have know where to start in sorting my alarm issues without the information found on this forum, so I felt the need to share my findings.
When I Pressed the unlock button on the fob it stopped, so clearly this was the alarm. As the alarm was silent it wasnt too much of a nuisance, but irritating all the same. I set about trying to find out what was the cause.
The obvious place to start was to press the button on the dash to disable the cabin sensors, but this made no difference to the problem. Thanks to the OOF I found a list of possible faults that I wouldn't otherwise have know about. The first and one of the simplest things to check was the bonnet pin. Using a voltmeter I found it was a push to make switch so I disconnected it, but the fault remained.
Next was the infamous powersounder, as I had read even if it had apparently stopped working, there could be a voltage draw from the car that could trigger the alarm. I removed it, but again it made no difference. Now I was struggling as 90% of the alarm issues I found were powersounder related. I moved on to checking the door sensors and as the interior lighting was reacting as expected to opening and closing all of the doors, I decided it was unlikely to be the issue.
After a week of living with this annoying fault, I went around the car checking and double checking the items related to the alarm. This is when I spotted the alarm strips on the rear side windows (boot side windows only found on the estate) I found that the wires just push on to the window using a press stud. I pulled all the connectors off and cleaned them with a cloth and a splash of WD40, then popped them back on. This was 4 days ago and the alarm (well indicators) hasnt gone off since.
My next task is to replace the secondary horn next to where I took the powersounder from. Ive already checked and found it is faulty, but the 2 pin connector does give voltage if I set the alarm off. Had I not had the drama with the persistant alarm, I would never have figured out how to fix this "silent" issue. If that works I dont think I'll bother fitting a new powersounder.