Disconnect battery and alarm goes off.. Help!

[robump]

Hi,

I disconnected the negative terminal on my battery to remove the stereo to fit a new head unit, however as soon as i take the terminal off the alarm goes off.

Does anyone know how to stop the alarm without having to reconnect the battery?

Thanks for your help!

[bacillus]

Stupid question but was the car locked when you disconnected the battery?

[robump]

No it was unlocked with the doors open, hmmm really puzzling!

[bacillus]

fwiw I didn't disconnect the battery when I changed my head unit. I also didn't disconnect the air bag wiring from the vent section so no air bag light on refitting.

[robump]

Ah ok, just i have been looking through all the guides and they say you should do, but is it possible to do it without diconnecting the battery? What could i break if u dont?

Thanks

[callis]

Mine goes off if i dont fully unlock everything including boot.

[bacillus]

Ah ok, just i have been looking through all the guides and they say you should do, but is it possible to do it without diconnecting the battery? What could i break if u dont?

Thanks

I think the reason folk disconnect the battery is because they unplug the air bag wiring and forget to plug it back in when the unit is installed, turn on the ignition and bam, the air bag light comes on in the dash.

You need vcds to clear the light.

[robump]

Ah ok, so if i dont disconnect that warning light wire then i should be ok?

[homesqueeze]

This happened when I changed my battery. As soon as I took the terminal off the alarm went off. Just use the key fob to turn it off. Press unlock when the alarm starts and it will go off. This did the job for me. It also went off when I reconnected battery again. Same applies for that. 

[DSG-GTI]

Ah ok, just i have been looking through all the guides and they say you should do, but is it possible to do it without diconnecting the battery? What could i break if u dont?

Thanks

I think the reason folk disconnect the battery is because they unplug the air bag wiring and forget to plug it back in when the unit is installed, turn on the ignition and bam, the air bag light comes on in the dash.

You need vcds to clear the light.

/\ /\ /\ /\

I agree with this fella... I have fitted a new head unit and didn't disconnect the battery, Just make sure you DO NOT turn the ignition on until everything is plugged back in 

[BlackGTI]

x2

[daboy3000]

Don't you just turn on the ignition 1 step and then disconnect the battery.  Something like that anyway.

[robump]

Thanks for all your help.. gonna give this a try today so will let you know how it goes.