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Flat Battery/alarm Weirdness

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Jumped into the GS this morning to go to work after it had sat idle for 4 days.

the remote central locking unlocked - key in the ignition and the steering wheel moved to position (a tiny bit slower than usual - i was soon to find out why)

Tried to turn the engine on and apart from the dead-battery click that was it. I had an almost completely dead Battery. :angry:

Soooo. As i didnt have time to fix it, i locked the car with the keyfob (it locked) and went to hop in the trusty (but much less refined) clio. As i went to do so the GS got extremely upset and started crying. Well..i assume it was crying it was more of a wailing, alarm-going-off noise. I unlocked it again with the keyfob and the alarm stopped.

'Ahhh' I thought, the alarm must be getting confused somehow because of the low Battery so this time i locked the car by key - the alarm went off again a few seconds later. I thought key-locking the car disabled the alarm? I guess not. I didnt particularly want to leave the car unlocked for the day so in deperation and because i was very late I got in the car and pressed the doorlock button from inside, then got out and closed the drivers door with the door handle held up. Hopefully that'll do for the time being.

Can anyone explain whats causing the alarm to go off (I dont think its a dodgy alarm that's caused the flat Battery, its the OEM one and it hasn't gone off overnight or while i've been in the house the past few days)

All doors and windows are fully closed, i can only suppose that the Battery is low enough to provide a dodgy supply to the alarm ECU which its interpreting as an intrusion.

Any ideas?

I'll have to try and charge it tonight. I'm guessing if once its charged properly, I can put my voltmeter across it and check that its around the 14v mark. That'd indicate that the charging circuit is working properly wouldn't it?

Thanks for any help peeps


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Something similar happened to mine about two months after I bought it.

I had used the car one night without any problems and then the next morning the alarm went off, so I went out and turned it off and all was fine, until I needed to use the car.

I opened it with the remote and when I put the key in the ignition the dash lit up, but the steering wheel didn't move at all, so I tried to turn the engine over and nothing happened.

My Battery was flat and it looked like the original one, which would've made it around eight years old, so I went to Halfords and bought a long life one and it's been fine ever since.

If you have the alarm that has a button on the key then it also arms/disarms by opening the boor or boot with the key, but if you have the alarm that has a seperate keyfob then the key has no affect on the alarm.

Alarms tend to go crazy when the Battery is very low/flat.

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Thanks eMJay. Its reassuring to hear from someone who's been through it.

My Battery has just reached its 8th birthday and it looks like the original. The car had occasionally been a little slower to start on cold mornings, but not enough to get me worried. I guess the Battery was on its way out.

Looks like a trip to Halfords tonight then. I think the Battery is so deeply discharged that it's probably fit for the bin anyway..

Wish it wasn't the same weekend that i needed to replace the central heating pump in the house though! :D

All the best,


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