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Alarm / immobiliser draining battery

Posted: Tue Dec 06, 2011 2:54 pm
by Malandro
Earlier this year we had an all-in-one alarm / immobiliser installed in our Bongo after it was nearly stolen from our driveway. The alarm is a Thatcham approved Hornet Maxx 1 which was installed by a fitter who came personally recommended.

Following a period of around 2 weeks non-use, we had a flat battery. Having no jump leads at that time we called the AA and they tested and then replaced the battery. This happened again about a month later and the AA replaced the battery free of charge thinking it was a dud. However, we noticed that the battery was getting very low after a week and I came to the conclusion that the alarm must be draining it quicker than it should. I phoned the installer and he said it sounded like we had an underpowered battery and in any case we should drive the vehicle fairly regularly to avoid the problem. The AA battery is a GBA 3075 but I've no idea what that means in terms of output and there are no other details.

This morning I was awoken by the alarm going off but the keyfob would not open the doors, the lights would not go on and of course the van would not start. I assume the alarm was draining the dregs of the battery. So my questions are:

1. Is that battery approppriate for a Bongo?
2. Is there a way to leave the vehicle alarmed for a long period without killing the battery? I could hook up a battery conditioner but we are about to move and will not have the luxury of a drive / garage to leave the vehicle plugged in?
3. Is there an easier way to immobilise the vehicle if it is to be left stationary for months on end?

Sorry for the long post....I'm not very technically minded and the girlfriend is now threatening that we should sell the van!!!

Thanks

Re: Alarm / immobiliser draining battery

Posted: Tue Dec 06, 2011 3:37 pm
by Muzorewa
That's the same alarm we have on ours. It shouldn't drain the battery, it should be using a miniscule amount of juice to run. Either the battery is duff or the alarm not installed correctly.

Re: Alarm / immobiliser draining battery

Posted: Tue Dec 06, 2011 3:42 pm
by Malandro
Mmm....interesting. The installer came well recommended!

What rating of battery should I have then? The one the AA installed is very small and helpfully has no information about its rating on it!

Re: Alarm / immobiliser draining battery

Posted: Tue Dec 06, 2011 3:55 pm
by wonkanoby
google is not getting much on it

bar a list were its at about 30 quid

and that seems well low for a bongo battery

which are usually 80 quid or more

Re: Alarm / immobiliser draining battery

Posted: Tue Dec 06, 2011 3:59 pm
by g8dhe
Humm, No alarm system should drain a battery in a couple of weeks!
What sort of vehicle is it Diesel, V6 or 2l ? Has it got a conversion at all, or any leisure batteries fitted ?
It sounds like you have something else draining the battery, the radio hasn't been left in standby or with a clock display left running ? If so that could be the cause, remove the front-panel if it is that type.
The only way you will be certain however will be to measure the current drain on the battery with a meter and then track down whatever is drawing the extra power.
The battery spec. doesn't appear in a Google search, but it is a common sort of battery found in quite a few cars.
To immobilise the vehicle you could always pull a suitable fuse or relay, in a V6 or 2l pull this MAIN relay found in the fuse box under the bonnet in the middle, its marked MAIN on top of the fuse box cover, that will remove all power from the Injectors and ignition system.

Re: Alarm / immobiliser draining battery

Posted: Tue Dec 06, 2011 4:06 pm
by jaylee
I've read on here the strip light in the back of the van when its on its way out (even when off) can cause a drain giving those symptoms..?

Do you have a leisure battery fitted?

Out of curiosity, is the siren on your alarm system self powered/has a back up battery so it triggers if the power is cut from the main/starter battery..?
wonkanoby wrote:google is not getting much on it

bar a list were its at about 30 quid

and that seems well low for a bongo battery

which are usually 80 quid or more
I'm thinking the same thing as Wonkanoby... There is a lot of info on here for the type & spec using the search facility for starter battery!!

Re: Alarm / immobiliser draining battery

Posted: Tue Dec 06, 2011 4:34 pm
by Malandro
The van is a 2.5L diesel and yes it has been converted and has a leisure battery. Everything seems to be in order with all of that though and I can't see that anything else is draining the battery. All was fine prior to the installation of the alarm!

Re: Alarm / immobiliser draining battery

Posted: Tue Dec 06, 2011 4:46 pm
by teenmal
Hi this GBA 3075 was fitted to a Corsa?by the AA.


http://www.gumtree.com/p/cars-vans-moto ... w/91008328

Re: Alarm / immobiliser draining battery

Posted: Tue Dec 06, 2011 6:05 pm
by g8dhe
Malandro wrote:The van is a 2.5L diesel and yes it has been converted and has a leisure battery. Everything seems to be in order with all of that though and I can't see that anything else is draining the battery. All was fine prior to the installation of the alarm!
Is the Leisure battery OK, when the starter battery is flat ? (I'm thinking load on the L/B and a split-charge relay welded closed?) - Incidentally you can always use a full leisure battery to put some charge back into a starter battery, sufficient to get you started once or twice.

Re: Alarm / immobiliser draining battery

Posted: Tue Dec 06, 2011 7:46 pm
by perros huevos
you will have to put an amp meter on to see what current is being drawn then start pulling fuses out till you find the one that is causing the drain.could be a relay thats energised thats causing it or even try disconecting the main thick cable to the alternator
chris

Re: Alarm / immobiliser draining battery

Posted: Wed Dec 07, 2011 9:34 am
by Malandro
The leisure battery seems to be okay and I don't think the siren has a back up battery - everything comes off the starter battery. But as I say, everything was fine till the alarm was installed!

Will try to get it going at the weekend and take it to an automotive electrician....I don't have a multimeter or anything for measuring current! Hoping its just an underpowered battery - anyone have an joy with those solar panel trickle chargers?

Re: Alarm / immobiliser draining battery

Posted: Wed Dec 07, 2011 11:00 am
by g8dhe
The cheap solar cell type that you plug in via the cigarette lighter are a waste of money (with the ignition off most cars isolate the cigarette lighter anyway!) however some of the rather more expensive photo voltaic systems can be quite effective these days but your talking several hundred pounds not a few tens of pounds!

Re: Alarm / immobiliser draining battery

Posted: Wed Dec 07, 2011 7:00 pm
by g8dhe
In discussion with another person fitting an alarm, the guidance notes suggested for fitting the Immobilser relay suggested picking up either the Ancillary circuit (ACC on Ignition) OR direct to +12volts. The latter is NOT a good idea as the relay will be operated 24/7 and would put a load on the battery I just wonder if your fitter has done this and not used a switched +12volt feed from the Acc circuit....

Re: Alarm / immobiliser draining battery

Posted: Wed Dec 07, 2011 7:18 pm
by mikeWalsall
It seems strange (as a layman) that a energised relay would quickly discharge a healthy diesel battery ..

I have a very simple home made deterrent on my bus ..

A normal relay .. ignition off ...a permanent live closes relay contacts .. warning LED flashes .... ignition on the relay opens the contacts .. LED stops flashing ..

I have had that on my Toyota for over six years .. also being Petrol it as quite a quite small OEM battery (If I recall less than 50ah) the motor as been left for extended periods several times with the relay energised and the LED continually flashing with no hassles .....

Re: Alarm / immobiliser draining battery

Posted: Wed Dec 07, 2011 7:30 pm
by g8dhe
A lot of standard automotive relays are 80Ω which means they draw 0.15 Amps (12/80), over 24 Hours that is 3.6 AmpHrs, your battery fully charged has about 95AmpHrs capacity (maybe as low as 75AmpHrs) so that's 95/3.6 = 26.4 Days so under month, if that was the only thing! There are usually a couple of other circuits that will be drawing current as well, my own rule of thumb is that if there is 50mA = 0.05 amps being drawn that's fine, anything more than that I would prefer to understand where that current is going - it may not be necessary!