Alarm Immobiliser

Got to take the car in for service tomorrow, so went out to start it up this afternoon. It hasnt been started for a week or so and had to open the door manually. As soon as I tried to start the engine, the alarm went off and I couldnt stop it or start the car by pressing the button on the key. What am I doing wrong - Help !!! Chris

Dont worry it's supposed to do that. It goes to sleep mode if you haven't used it for a while, so next time, manually unlock the door, then quickly press the unlock button on the remote key fob, and everything will be fine.

No joy I'm afraid - it seems the battery might be low - would this affect the alarm system ? Is it possible to just connect a charger to the two terminals with everything switched off, or is charging a more complicated procedure ? Chris

A low battery will definitely affect the alarm. Do you mean the emergency terminal on the fuse panel, or the battery terminals themselves? Either way, a trickle charger can be connected to either.

I was proposing to attach the two charger leads to the two terminals on the battery itself - is this a safe procedure ? Chris

That's how it's done. Just make sure you get them the right way round!

Also, the instructions on my charger say that batteries should not be charged while still connected to the cars electrical system - but if I disconnect the battery, will this not affect computer settings etc ? Chris

You won't do any harm by leaving the battery connected. Just switch off as much as possible. If you disconnect the battery you'll have the alarm siren go off - see the Battery Change DIY in the Technical articles section.

Thanks Richard - seems to be working alright - OPC will be extremely grateful to you for ensuring they do not miss out tomorrow on their 'very reasonable remuneration'. I must remember in future to use the car more often ! Chris

Fingers crossed that the battery will be OK. At 3-4 years you are entering the time when the original battery will be getting towards the end of its life, so it's worth keeping an eye on it.

The instructions on my trickle charger state that you should NOT connect the negative wire to the negative battery terminal. So I connect it to the length of bare metal running to the left side of the negative terminal (beside one of the horns), negative first, then positive.

I have always found the safest way to connect a battery is. Positive First, then Negative second. That way, If your spanner touches any of the body work you wont get a short / sparks etc. Something best avoided arround batterys. Regards.

Mine never works like that -- the alarm always goes off. Anyone else have this problem?

Insert key in door. Turn it so that the interior lights come on. Keep the key in the door and press the unlock button. That will prevent the alarm going off.

That's odd, that's what I did yesterday and it worked. Maybe the activation process changed over time? You're right, my mistake [8D]

Yes - if I leave mine locked for more than 5 days the alarm always goes off - as soon as I turn the key to the unlock position.

I can't remember if it works like this on the 996, I hope it does and I'm sure I used to do this.. When you come to your car, Lock the car with the key then the keyfob becomes active and works fine... this is how I manage to do it with the current motor.. garyw

Maybe that's what I'm doing?

Thanks Gary - but I've tried that too, with the same result. I haven't got any fault codes in the alarm control module, and I just put it down as a quirk - maybe it's just on older cars. What year is yours, Paul? It doesn't bother me too much to be honest. I use the car every day, and it's only when I go on holiday that it happens. You learn to be ready for it, and it's amazing how quickly you can unlock, open the door, and switch on the ignition.