V50 Battery/Electrical Power Issues
 

Afternoon all,

Last night I went to start my V50 D3 2011 and as I turned the key to III it all went dead. I assumed I had foolishly let the battery go flat so had it jump started and it eventually started after 20 minutes of donor power.

I then drove home, when coasting and going for a sharp turn all electrical power cut out but engine stayed running. I then got home and it promptly died electrically.

This morning I fitted a new battery and cleaned off all the terminals. I noticed a lot of heat damage around the positive terminal, even exposing some of the Battery Management System. The positive terminal clamp was only finger tight, and there was residue on the battery around the terminal.

New battery fitted and wires temporarily insulated with tape, it started fine, but after running for 5 minutes the positive terminal clamp was already warm.

Has anyone experienced this before? I assume the car cut out whilst driving because of high electrical load from the steering pump.

Next step to replace the exposed BMS wire and maybe the positive terminal wire?

It would appear dodgy connections are the issue and this will cause heat. Undo them all and clean the terminals up witha fine wet n dry or sandpaper. Stick a dab of grease on and should be ok. First thing to try in your situation would have been the battery voltage AFTER checking the terminals.

Hi
Worth checking the alternator output, could cause all those issues. Also they are prone to an internal short that can drain a battery

Iain

Hi both,

Thanks for your replies. I cleaned up the terminals and fitted the new battery, all was fine for 3 days and then this morning same issue with car cutting out as soon as I tried to turn the wheel and all electrical power gone. Whilst the car was running on the weekend the terminal connection was still getting very hot.

The battery terminals were tight and clean, so alternator is my next point of call. It is going into a local good garage for investigation and hopefully the alternator is the fault.

Will update in due course!

First thing to check when that happens is the battery voltage of course? If voltage is still good (+12) then the issue lies elsewhere clearly. Did you do this?

Hi Pete,

I did not with the original battery as it had obvious damage and fluid leaking around the terminal, so changed it assuming it was very much dead.

As the car was dead around 100m from the garage this morning and not where my multimeter was I have passed it on to them.

Hi all,

Fault found - the alternator was faulty and putting out 17V(!), this was then blowing the terminal fuse at peak and causing the total failure.

New alternator and soldered fuse joint and we are back on the road. Thanks all for the help.

How did you get on? Also worth noting that some garages put things back wrong so make sure nothings rubbing on steering column etc and no live wires exposed anywhere that could be shorting.