Alarm problem

[brickers911]

Hi all
My alarm keeps going off when i lock the car, presumably a sensor issue, but which one? I have INPA and cable off of ebay which I have had some previous success with wheel sensor and brake pressure sensor fixes but not an expert. I have looked but can not find anything in the menus to indicate where to go to to find intruder alarm, only thing near was something to do with the immobiliser.

Any guidance appreciated

 

[RustyZ4]

Most likely the bonnet sensor, its very common for that sensor to be faulty and cause the alarm to keep going off

 

[brickers911]

Is there anyway of testing it?

 

[markplant]

Is there anyway of testing it?

You can just unplug the bonnet switch, an see if that cures the alarm going off, if it does either replace or leave unplugged , it's at the rear of engine where the 2 braces meet

 

[Yorkie Z]

I drowned mine in WD40, seems to have done the trick.

 

[brickers911]

Thanks, just come back in from playing around with the switch, I carefully prised it apart cleaned the contacts with fine emery and reassembled after cleaning with contact cleaner. Seems to have done the trick so far. Its a normally closed switch so activating it will make it open circuit, the same as unplugging it to test.
Thanks for pointing me in the right direction

 

[Lance]

A new switch from BMW was £11 a few years back, I guess it's still under £20 now.

 

[cj10jeeper]

About £7 on eBay as it’s a standard on a dozen models

 

[mr wilks]

Not unusual for first signs to coincide with big temp swings , its one big bonnet to expand & contract

 

[brickers911]

A new switch is 37 quid now!!

 

[idej_z4]

I had the same problem...became a bit of a joke at my workplace. I removed and cleaned it, which worked fine for me.

 

[Z4 COUPSTER]

:wink: I might try cleaning mine. After reading this. It's been off for 3yrs.