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Just after some advice if possible. I posted that my battery was flat a few weeks back, so I bought a new battery and all was good.

However, I haven't driven the car for about 4 days and the battery is flat again, no dash lights, won't open via the fob etc.

How can I easily find out what is wrong? I'm no expert but I'm guessing something is draining the battery when the car is off??

If anyone could suggest what I can do, it would be really appreciated.

Just had the turbo done on my X3 so could really do without an expensive fix

Had the same earlier this year and it was alternator!

Think it was around £300 fitted at local indy!

MefiEcosse wrote: ↑Mon Jul 17, 2017 6:37 pm Had the same earlier this year and it was alternator!

Did the battery go flat after being driven or while driving? Strange thing is, it has been fine for weeks now and then just gone flat over the weekend

Yeah, I changed the battery then used car 2 or 3 times before the car died on me, it was about 3 weeks. I'd get it tested before doing anything else.

MefiEcosse wrote: ↑Mon Jul 17, 2017 7:10 pm Yeah, I changed the battery then used car 2 or 3 times before the car died on me, it was about 3 weeks. I'd get it tested before doing anything else.

Test the alternator?

Mine was tested by Green Flag when the came to rescue me!

Get a volt meter (or a voltage indicator, cigarette lighter ones are dead cheap, like this). When the engine starts you should see around 13.5 - 14.5 volts being pumped out by the alternator (mine is 14.2V) - if it's under that range, I'd take it to a trusted indy for a check.

Check this thread also

markeg wrote: ↑Mon Jul 17, 2017 10:38 pm Get a volt meter (or a voltage indicator, cigarette lighter ones are dead cheap, like this). When the engine starts you should see around 13.5 - 14.5 volts being pumped out by the alternator (mine is 14.2V) - if it's under that range, I'd take it to a trusted indy for a check.

Check this thread also

Thanks, just bought one. Gonna get some jump leads and try and start it after work.

About 3am (as you do) I woke up and recalled a neighbour telling me my side lights were on a few weeks back.

I didn't think much of it at the time but the headlight control wheel on the dash was on the automatic lights setting, engine was off but sidelights were visually on.

I turned them off and the next time I drove the car, I put lights to auto, turned off the car and when I checked they were off...as you would expect.

I'm now wondering if the sidelights had again, mysteriously been on, even though the car was turned off.

Can't work out why this would happen but does explain how the car was fine for weeks but then after not driving for about 5 days, the battery is flat because something is draining it. When I use it everyday/every other, there is enough charge to start the car.