Car Alarm Sounding Off!!

[madmax26]

Happy New Year!

My Daughter's 2008 9-3 Aero has started to act up!

Several times now after parking and locking the car the alarm system has has gone off! There's no wind blowing, no movement. She unlocks, then locks the car to reset it.

Any ideas?

Mark

[chris aka zaphod]

First things, first.
What's the condition of the car's battery?

[madmax26]

Hi
The battery was purchased just last summer.
She has no other alarms or faults!

Mark

[sgould]

There are two different alarm systems you could have, basic which uses the car horn and indicators, and a "better" one with a body motion sensor and glass break sensor.

Either way the system is triggered via the data bus via the logic in the Body Control Module.

So many bits involved, I think you have to get the codes read to get to the bottom of it.

[madmax26]

Thanks!

So it isn't like the alarm on my old 9-5 which had separate batteries that could fail and cause the alarm to go haywire!

We will wait and see if it continues to cause trouble, and if so we'll bring it to the dealer to get codes read.

Tanks again for the help!

Mark

[jimbo]

POSSIBLE THE ALARMS INTERNAL BATTERYS  IS GOING.LOOK UNDER NEARSIDE WING YOU WILL SEE THE ALARM
BOX. TO REMOVE YOU NEED TO JACK  UP LEFT HAND WHEEL REMOVE THE BOLT HOLDING THE WHEEL ARCH COVER AT THE FRONT  OF THE CAR IS THE ALARM BOX HELD ON WITH 2 X10MM BOLTS.REMOVE THE WIRING  BY PUTTING A SMALL SCREWDRIVER IN THE GAP IN THE RED PLUG.WHEN YOU TAKE THE UNIT OFF. YOU MAY BE ABLE TO TAKE IT APART IF IT IS HELD BY SCREWS IF NOT USE A DRIMEL TOOL
TO CUT IT OPEN YOU WILL SEE THE BATTERY'S THAT NEED REPLACING.WHILE YOU ARE GETTING THE PARTS YOU CAN PUT THE CAR BACK TOGETHER AND RUN WITH OUT A ALARM TILL YOU GET THE PARTS
YOU NEED TO FIX THE ALARM

[chris aka zaphod]

Sorry, yep. Should have typed car's alarm battery/ies.

[sgould]

On the newer 9-3, it's nothing like the old models.

The separate alarm, if you have it is in the boot on the right hand side.

[madmax26]

So on a 2008 9-3 there's a chance that the alarm is in the boot (trunk) on the right hand side?

I'll check it out in the morning and let you know!

Thanks for your help!

Mark

[sgould]

I've only seen a blob on a diagram.  It may be round the wheelarch, or I'd may be under he floor. I can check further when I get back to my laptop with the workshop manual.  Around lunchtime, maybe.

[sgould]

If you have one, this is where it is and what it looks like.