GTI Charging

[Rik762]

I have just changed my Blue GT for a GTI and have noticed something that puzzles me.
I have to leave my car for over a month at times and have always used a CTEK charger to keep the battery up to scratch. I have noticed with the GTI that when the CTEK is connected I can hear a relay ( I assume ) or two activating every 30 to 60 seconds. I can't recall hearing this with the Blue GT.
Has anyone else had a similar experience and any thoughts as to reasons / problems ? I am a bit wary of leaving the charger on while I am away.

[Philmar]

The blue gt uses an agm battery & your smart charger would have been switched to that mode of charging.Does the gti have a conventional battery or a agm battery this may be the problem.

[Rik762]

I would suspect that the GTI would have a similar battery to the Blue GT with both of them having the Start / Stop system. I don't know for sure of course as the darned thing is deep in the boot and a bit inaccessible.

[Ricmondo]

It's regenerative braking that may be the issue rather than start stop.

[4StringBass]

Are you connecting directly to the battery?

[Rik762]

No, I am using the proper connection points under the bonnet.

[4StringBass]

I don't know what it's like on VWs, but on BMW bikes if you connected the charger via the power socket you need a CANBUS enabled charger to keep the socket awake to allow it to charge. You can just connect the charger in conventional mode straight to the battery without issue. I'm guessing though that you've connected it to the jump starter posts under the bonnet if the battery is in the boot?

[Rik762]

That sounds correct.

[Guy]

With your GT were you connecting directly to the battery terminals? With the GTI arrangement I think you can't by-pass the Battery Management system by connecting directly to the battery. That might be a difference.

I use a Ring RSC8 intelligent charger just for occasional winter top-ups lasting a few hours but I don't leave it connected continuously. It's current and voltage limited but the maximum voltage it puts out is 14.4V which may be a bit low for the stop/start battery type since the car's own charging system will use up to 15.0V.

Incidentally my GTI only has a single positive (red) terminal under the bonnet. You have to clip the negative charging lead to a suitable earth point - eg engine block. Does yours have the same arrangement or have you got both positive and negative terminals?

The GTI arrangement was a bit of a heart stopping moment for me. When I went for a test drive the 6C GTI was very new and the dealer only had the GT (which was very nice). I carefully checked under the bonnet for the battery location to ensure I would be able to easily keep it topped up in winter. So I ordered a GTI and then read that the battery was in the boot. Panic set in but by then the dealership had a GTI in stock at another outlet so they checked and confirmed the under bonnet arrangement!