[DaFlake]

Quote: Originally Posted by oldmots (original)

I agree, without the battery, all kinds of stray currents develop which can wreak havoc with chips. It is not smart to remove the battery and run the motor, sometimes you will be lucky, other times, you will fry stuff. I have seen alternators melt down and smoke in shops where characters did this.

Hmmm... In my efforts to support my quote above I have found that I am in the minority and although I have done this and not had any problems, I am considered lucky.

So, let me go on the record and retract my previous statement.

The best and only method that should be used to test and alternator is by multimeter. It is still a very simple thing to do.

[boobels]

Quote: Originally Posted by DaFlake (original)

It is a fairly common part to fail on any car. 40K does seem a little shy, but I have replaced them at as low as 15 on some cars. 300 pounds seems very high for the cost, who is doing the work? You didn't take it back to the dealer that didn't know something was wrong with it did you?

If you are out of warranty, I highly suggest that you find a good local garage.

Nah it is in the local indie garage, not going back to a stealership, especially after they couldn't find the problem given 4 days of looking!!

Thanks everyone for your help and advice, hopefully tomorrow I can go back to enjoying my car

[THEWORKSMINI]

Which dealer did you take it to? Name and Shame time I think! Testing the alternator is a very easy job in a BMW dealership, the GT1 has a complete test schedule too! What many people forget is that a good voltage output from an alternator doesn't necessarly mean it's ok. The charge current under load should be checked too!