[mick14]

Hi Guys I have been having charging issues with my 08 R50 for the last 12 months or so. The problem is that the batteries drain after about a week to 10 days. I've had the alternator out and tested twice (came up fine on both occasions but I replaced the regulator last time - just in case)
Anyway the batteries are still going flat (batteries have been tested and are good)
When driving the car the volt meter continually dances around from 12 to about 13.8 volts.
It sort of sounds to me like the alternator cable issue that the 04/05 models had where VW did a recall and replaced them but as I said this is an 08 model so it shouldn't be the issue.
As you can imagine this is starting to get me down :anger: so any advice and help would be greatly appreciated !
Thanks,
Mick

 

[hedditch]

When driving the car the volt meter continually dances around from 12 to about 13.8 volts.
It sort of sounds to me like the alternator cable issue that the 04/05 models had where VW did a recall and replaced them but as I said this is an 08 model so it shouldn't be the issue.

Mick, although I don't have a V10, the fluctuation in the voltage sounds really suspect. My volt meter sits rock steady at 14 volts (nominal)from start up. After a while it drops back down a little, however it is very stable and seldom if ever, "dances".

I think you are on the right track. Time to do some cable chasing.

Stuart...

 

[mick14]

Anyone else ? Surely there must be others out there with a similar issue?
Mick :???:

 

[schootsie]

Sorry but no dancing, Sometimes the battery light will stay on for longer than expected (say1 0 to 15 secs) with the voltmeter reading around 12 v but then it flicks straight up to 14+ v over the next few seconds. Only happens every now and then and not necessarily after a heavy battery load.
John

 

[warrenza]

I am sure you have thought about this

"problem is that the batteries drain after about a week to 10 days" this sounds like something drawing too much current. Have you tested how much current the car is drawing when it is "sleeping" compare this against other R50's on this forum.

Are the batteries getting fully charged by the car? compare the voltage after a drive to that if the batteries are connected to a charger.

Have you had the batteries load tested?

Lastly maybe get a battery regulator installed, configure it so that battery 2 is disconnected from the car when it is switched off. Battery 1 could be changed to a deep cycle to cope with the permanent current draw down.

 

[kev11e]

G'day
When starting battery is flat, turning the key anticlockwise for a few seconds connects the two batteries so starting is possible, so there is already some kind of isolator installed.

 

[mick14]

Thanks for the replies guys, yes the batteries have been load tested and it has also had a current drain test (overnight). I'm 99% positive that its a charging or cable or voltage control unit issue.
Mick

 

[Bails]

Mick I haven't had your issue but I know that under the passenger seat , where the main battery is you have a set of relays that act as isolators. I did have the situation where one of the relays had flipped one way and did not return causing a fault. You may have this PDF on the electrical system if not maybe it will assist.