Effing Battery

[milu]

Had all this last year on my MB CL..

I had a new battery on my Vantage in the summer after the other seemed to stop holding charge. It was original I think
I us a Ctek charger..mxs 5.0.
Recently the charger has been showing the red error light after a day or so. I believe this indicates the battery has failed the voltage hold test?

I guess this would suggest a drain of some sort or my Ctek is faulty.

Anyhow because of this I switched off the Ctek last weekend(but still connected) and this morning I have a battery down to 2 volts!

So I've had to do the parcel shelf/emergency boot release shuffle and also try to get the battery to charge. However these modern chargers won't start if the voltage is too low. I've tried 2.

Any tips on jump starting because I was struggling to find a good earth?

What a pain in the backside.

[Jon39]

You probably already know this Mike, but I would try jump leads from another vehicle (engine running), connected to the (jump) terminals under the bonnet (forward offside).

[milu]

Thanks
The positive connection is readily apparent. However getting a good earth point not so much. The area suggested in the manual wasn't much use with my quite large crocodile clips on my heavy duty cables.

[old phart]

I don't know if it will transfer over but with some drone batteries I've put a good one in the charger and once the process has started I quickly swapped in a dead one. The charger had a bit of a lag in it so it stayed in the charge state.

Or maybe connect jumper cables, turn on charger, wait till it indicates charging, disconnect jumper cables and see if it remains charging.

[milu]

That’s my next move I think. I’ve got a charger at work which might go but not sure. Otherwise it’s a donor battery to fool it.

[milu]

Update:

Vantage 1 Ctek 0

Finally got a good charge in the battery using another charger. Disconnected Wednesday evening and left alone. Charge still ok this morning and have done about 120 miles today so should be brimmed now.

Either my Ctek wasn't charging much before going into error mode or even worse was actually drawing current out of the battery whilst connected. It was about 5 years old.
I've bought a replacement so will see how that goes.
Thinking I might go direct to battery with the new charger rather than using the quick connector in the boot

[ds666]

Lidl

[milu]

ds666 said:

Lidl

Not sure if you mean buy one from Lidl

However the one I did use in the week was an Aldi special from a few years ago. I've got a AA branded one now. £20

[Turn7]

Caterhams are no different.....

Parasitic discharge caused by the immobiliser flattening the battery......

[Matt_E_Mulsion]

Are you sure that it is your ctek charger that it knackered, rather than it being a battery drain of some sort?

[milu]

Matt_E_Mulsion said:

Are you sure that it is your ctek charger that it knackered, rather than it being a battery drain of some sort?

Not 100% sure of anything yet. But the CTEK was connected to the car whenever it was stood for a while. Recently I would find it in error mode,which of course could be the CTEK seeing a fault.
However last week when the battery was very low and the CTEK connected it still went into error after a short while,long before the battery was in a highly charged state. It took 48 hours to charge with my Aldi version,at which point the charger switched into maintenance mode. No errors showing.
As noted above there didn’t appear to be a significant voltage drop from Wednesday to Saturday when left alone.

I’ll just keep an eye on it.

[BlackV8]

I had two Ctek mxs 5.0 going into error mode after a day or two. I was pretty sure the battery died but a friend told me he had the same issue with his one. Connected an older Ctek mxs 3.8 and surprisingly after two days the battery was properly loaded. Both two year old Ctek mxs 5.0 where changed under warranty and working flawless since then. Looks to me that there was a faulty production line out there ...

Cheers

[milu]

Thanks
Seems to fit with my experience