Volvo Owners Club Forum

Volvo Owners Club Forum (
-   S40 / V50 '04-'12 / C70 '06> / C30 '07-'12 General (
-   -   C70 alarm triggered by outside vibes (

Distendo Mar 5th, 2019 19:01

C70 alarm triggered by outside vibes
'06 C70 frequent false alarm

The alarm can be triggered by vibration from outside: passing (loudish) motorbike or lorry, etc.

Sometimes it just goes off for no apparent reason: I understand from other posts that this can be due to a duff siren battery et., however, I want to concentrate on its being over-sensitive for now...

No dangling wires etc. in the passenger compartment.

If I could find the ultrasonic (I assume) transmitter or receiver, I'd try covering either with some light material to try and mute the sensitivity.

Any bright ideas?

rowdy Mar 5th, 2019 19:34

Have you not got the reduced guard function on your alarm? If so have you tried it and does it make any difference?

This is of no help whatsoever, but two doors down from my parents own a v50 similar to mine, and when I operate my central locking it triggers the alarm on that car.

Distendo Mar 11th, 2019 18:20

Thanks for the reply.
It would appear not. I've been through the menu and as far as I can see there's no alarm options.

BTW, I've just discovered it's a microwave set-up, not ultrasonic. Supposedly so it works with the roof down... :confused-smiley-013 So I guess it'd be back to the tin-foil (with matching hat).

emy Mar 11th, 2019 22:59

My v50 does the same, if I do not disable it when I leave the car, the internal movement sensor triggers the alarm. If is too sensitive or defective, I do not know.
I do not mind deactivating/disable it. Every time I disable it, I get info. as "reduced guard, see manual"

phil1968 Mar 11th, 2019 23:23

There is a button up near the map lights that reduces guard?
I was getting random alarm triggers on mine, replaced the alarm siren internal battery, that lasted about 10 months then I got the same symptoms again, ended up replacing the siren module with a new one, has been fine for the last 18 months.

Bioly1975 Mar 12th, 2019 14:33


could be issue with low battery in side the siren module

scout70 Mar 19th, 2019 14:10

My last mobile phone if left in the car used to set the alarm off!

All times are GMT +1. The time now is 15:29.

Powered by vBulletin
Copyright ©2000 - 2019, Jelsoft Enterprises Ltd.