MK5 Golf GTI

All Things Mk5 => How to Guides / Troubleshooting => Topic started by: robump on November 03, 2012, 12:24:49 pm

Title: Disconnect battery and alarm goes off.. Help!
Post by: robump on November 03, 2012, 12:24:49 pm

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!

Title: Re: Disconnect battery and alarm goes off.. Help!
Post by: bacillus on November 03, 2012, 01:07:12 pm

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

Title: Re: Disconnect battery and alarm goes off.. Help!
Post by: robump on November 03, 2012, 01:11:47 pm

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

Title: Re: Disconnect battery and alarm goes off.. Help!
Post by: bacillus on November 03, 2012, 01:27:52 pm

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.

Title: Re: Disconnect battery and alarm goes off.. Help!
Post by: robump on November 03, 2012, 01:31:09 pm

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

Title: Re: Disconnect battery and alarm goes off.. Help!
Post by: callis on November 03, 2012, 02:45:30 pm

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

Title: Re: Disconnect battery and alarm goes off.. Help!
Post by: bacillus on November 03, 2012, 02:52:33 pm

Quote from: robump on November 03, 2012, 01:31:09 pm

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.

Title: Re: Disconnect battery and alarm goes off.. Help!
Post by: robump on November 03, 2012, 02:54:21 pm

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

Title: Re: Disconnect battery and alarm goes off.. Help!
Post by: homesqueeze on November 04, 2012, 10:35:30 am

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.  :happy2:

Title: Re: Disconnect battery and alarm goes off.. Help!
Post by: DSG-GTI on November 05, 2012, 06:07:29 pm

Quote from: bacillus on November 03, 2012, 02:52:33 pm

Quote from: robump on November 03, 2012, 01:31:09 pm

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  :wink:

Title: Re: Disconnect battery and alarm goes off.. Help!
Post by: BlackGTI on November 05, 2012, 07:43:40 pm

x2

Title: Re: Disconnect battery and alarm goes off.. Help!
Post by: daboy3000 on November 06, 2012, 12:18:02 pm

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

Title: Re: Disconnect battery and alarm goes off.. Help!
Post by: robump on November 09, 2012, 10:58:52 am

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