Hi All, just found this while researching and seems a very similar problem on my SC over the last week or so. My battery was new 6 weeks ago and car works perfectly over the day, just initial startup.

Quick technical question, Im picking up a multimeter off a friend later so can check if theres power drain. What should a fully charged battery read and what is acceptable draw when factoring in alarm and any other aux systems that need power?

hi paul and welcome to the forum..

this thread might help with your questions,

http://www.fullfatrr.com/forum/topic15891....tery+drain ... - .- -.




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Thanks, will check to see if its FSR. Hopefully it will be as it looks identical procedure to my old 5 series (strange that the FSR looks identical and prob is a BMW part. but never used to drain batteries on the E39 5 series, just stop the fans working)

This may not be much use but here we go I had a similar problem with my p38 and the problem turned out to be a corroded cable from the alternator to the battery and because it was internal corrosion it wasn't obvious and also it as in the problem would move - so as the cable flexed a little good connection then poor. Before installing new cables I bobbled up from the starter to alt and alt to battery might be worth sticking a meter over the cables. Good luck anyway

Have left the car out in the cold since considering it might be the hidden, plugged in phone charger and touch wood, it has fired up crisp and clean each time so far since disconnecting the phone charger.

I did wonder if it might be a bad connection with the battery too though... There's time for the phone charger theory to fall flat yet though!

Interesting that when cold it has no problem thinking copper wire and cold improves conductivity a lot - - Hopefully it is cured

Sorry meant to say it sort of rules out any probs with the battery in my opinion

My wife's car. She says it has never happened when she starts it. I went to start it up this afternoon after she'd been out in it. It did it again!

Car went into garage yday and mechanic rang me in the afternoon saying they'd found a 10amp battery drain and had also located a tracker device installed in the boot of the car (not something we've been subscribing to/ didn't even know it was there). He said those units can drain the battery and so has disconnected it, trickle charged the car and hopes the problem will be solved.

We shall see...

Hi, the start up problems persist with the car despite the Tracker device having been disconnected in the hope, that was the cause for a 10Amp battery drain.

Whilst driving home on the motorway in it this morning, my wife phoned to tell me the car lost power on the motorway and at the same time she got a Reduced Engine Performance dashboard warning. That fault cleared after the car was switched off and re-started.

Alternator then possibly causing the issue? If its draining the battery and then not charging it when running it could cause all sorts of weirdness once running.
Specialy when heated seats, screens, ICE, Lights... are involved they REALLY drain the battery. FFRR MY06 facelift With TDV8 Alloys Zeros/ATR's
Mantec Sump Guard, Rigid Load liner, MY10 BT upgrade.

So the car is going back in for a third time later today re this issue.

I've asked them to change the battery under warranty (which was my original request) and also now the alternator under warranty on the basis that I've humoured the so far time consuming, inconvevnient, unsuccessful and in vain efforts to detect the source of the battery drain, including unnecessarily cutting the power to/ knackering the Tracker device.

My rationale for the requests is that aside to the disproportionate amount of time and inconvenience, this is now a safety issue as the car lost power in the fast lane of a motorway whilst my wife was driving our children in it.

loosing power in that situation is indeed very dangerous, go and kick ass Ryan..  ... - .- -.




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If you look back an alternator failing on a 2007 car is a common occurrence.