2003 Astra Convertable - Car Alarm

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Fri 20 Dec 2013 21:42
2003 Astra Convertable - Car Alarm - MaurH

Hi, I recently purchased a 2003 Astra Convertable and am very pleased with the car. But the alarm occasionally activates when I start it. There was only one ignition key when I bought the car and this key sometimes came apart. So thinking that this may be the problem I had another key made, but the problem is still happening. I can unlock the car using the remote, I can turn the key in the ignition, but when I start the car, the alarm goes off. When I then take the key out of the ignition, lock and then unlock the doors, the alarm stops.

No fault code is coming up on the monitor and all old fault codes have been cancelled out. Any help would be appreciated.

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Fri 20 Dec 2013 22:12
2003 Astra Convertable - Car Alarm - elekie&a/c doctor
The most common issue with this and other vauxhall models, is the alarm power sounder internal battery.When this fails,it causes many erratic false alarm conditions.It is located in the left front wing,behind the plastic stone guard.Most owners just have it disconnected and removed.This does not affect the cd locking or immobiliser functions.hth
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Fri 20 Dec 2013 22:27
2003 Astra Convertable - Car Alarm - MaurH

Thank you for your prompt reply. I will take your suggestion to the guy who has been trying to sort it for me....it may have to be in the new year now though.

Just a couple of questions, will disconnecting this 'power sounder battery' mean that the alarm will be de-activated and will not sound if the car is tampered with? or can the battery be replaced?

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Fri 20 Dec 2013 22:36
2003 Astra Convertable - Car Alarm - elekie&a/c doctor
the battery is fitted within the sealed power sounder.they can be taken apart but this usually results in wrecking the plastic casing.I think you will find there is a normal horn alarm sounder fitted in the scuttle panel,below the wiper linkage.this is in addition to the power sounder.
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Sat 21 Dec 2013 07:56
2003 Astra Convertable - Car Alarm - RT
The most common issue with this and other vauxhall models, is the alarm power sounder internal battery.When this fails,it causes many erratic false alarm conditions.It is located in the left front wing,behind the plastic stone guard.Most owners just have it disconnected and removed.This does not affect the cd locking or immobiliser functions.hth

It may affect the insurance though !

As said, it's a common issue - their life does vary, mine used to need replacing every 2 years but that seemed to be one of the worst.

The alarm sounder itself needs replacing to change the battery, it's not a service item, although a search of Astra forums will show that a few have taken the sounder to bits, changed the internal battery and then reseal the sounder casing - or get one from a Vauxhall dealer, last time mine was about £60 but it was 6 years ago.

Edited by RT on 21/12/2013 at 08:03

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Sat 21 Dec 2013 10:58
2003 Astra Convertible - Car Alarm - MaurH

elekie&A/C doctor and RJ, thank you so much for your information, it sounds as if this could be the problem and the parts dept of my local Vauxhall dealer agrees that it is the most likely. The price for this power sounder has gone up some since you bought the last one RJ, it's now £91.80 incl Vat, plus fitting :) but I will get the local garage who services my car to fit it, which will cheaper.

I did wonder why a fault code didn't show though, but maybe it doesn't for this problem.

Anyway I will sort it after Christmas and will post back when the problem is resolved.

Thanks once again for all your help. Have a Very Merry Christmas.

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Sat 21 Dec 2013 11:09
2003 Astra Convertible - Car Alarm - RT

Give Autovaux a call - they're good with discount prices on genuine Vauxhall parts - the sounder isn't listed on their website but they can usually do a deal somewhere.

www.autovaux.co.uk

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Sat 21 Dec 2013 11:32
2003 Astra Convertible - Car Alarm - MaurH

Thanks RJ. I have called Autovaux and the price is £75.55 plus £3.76 first class postage. So it's going to save me just over £12....which will go towards the fitting.

Thanks again for your help.

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Sat 28 Dec 2013 11:46
2003 Astra Convertible - Car Alarm - MaurH

Good morning,

Before I purchase this part for the alarm, I have another little problem which may or may not be associated. When I unlock or lock the doors of the car using the remote, the indicators...front and rear.. flash on the passenger side as they should, but on the drivers side they only flash now and again. Is this part of the problem with the alarm or a different one?

I'd be grateful for any help.

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Thu 19 Jan 2017 23:58
2003 Astra Convertable - Car Alarm - Ross Russell

Hi

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Fri 20 Jan 2017 00:03
2003 Astra Convertable - Car Alarm - Ross Russell

Hi know this maybe late, but my father in laws 03 plate astra convertible has had the same problem for years. Following a recent cold spell the main car battery packed in. Since replacing the main battery the alarm hasnt sounded. After speaking to mechanic friend he suggested it could relate to drop in voltage from main battery no working correctly. Hope this may help others

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