960 Alarm/Immobiliser - Rain Triggering

I've been meaning to raise this for a while. When I set the alarm/immobiliser on my 1996 960 3Litre (CD spec) it works fine except that heavy rain triggers it. If the alarm/immobiliser happens to be set when I start washing the car then hosepipe spray over the windscreen area also triggers it. This means that if I've got to leave the car anywhere for an extended period (like all day) and rain is forecast, I just have to lock it with the key at the drivers door - this leaves the doors and boot locked, but the alarm/immobiliser is not set, which effectively means that the car is less secure. Has anybody else experienced this and are there any ideas about how I might overcome the problem? StanC

Hi, Maybe the volvo guard window sensor is faulty or too sensitive.. HAve you had the codes checked at all? That would be my first step.. Also, I remember someone telling me that the alarm on the 960/V90 was a little too sensitive and there is a relay under the glovebox related to this.. Des. . . ;)

Thanks Des. I haven't had the codes checked, so I'll do that sometime in the next month and let you know the outcome. I will also try and find out more about the relay . . . . Stan.

Hi, I think it must have been James (foggyjames) that was telling me about this relay thing but I have, unfortunately, forgotten the details.. :( Des. . . ;)

I had exactly the same symptoms on my Surf. I got the guy who installed the alarm to sort it, he said it was a faulty bonnet catch causing a short which affected the bonnet alarm sensor. He changed the bonnet catch, its been fine the last week of rain. HTH