XSeries-forum

[quote="X5Sport"]
[quote="Smeeagain"]
Can you do the test at the charging points under the bonnet?
[/quote]

No.  You need to disconnect one side of the battery and put an ammeter in circuit, or run the BMW test system on the car.  I don't know which part of the software suite does it though.

Richard
[/quote]

So to do that you'd need to have the boot open - will the car still go to sleep ? Im thinking for example the interior light will still be on ?

I've got the same thing at present. 135mA draw at rest. You have to test at battery as Rich has said but if you activate the boot lock while it's open it will trick it into thinking it's closed and start the sleep process.

My old E53 just went to sleep even with the boot open.  Lights went out etc.

Richard

I'm having problems with my E53, I just don't do enough miles, I'm thinking of getting one of those battery chargers that charge and condition the battery, 1.5 miles to work and back every day just doesn't do it.

Good idea.  It will save you a good deal of hassle.  You could always walk......

Richard

so what is the FSR .....?

[quote="Smeeagain"]
so what is the FSR .....?
[/quote]

Final Stage Resistor aka hedgehog.

Google it and you will find plenty of threads on it on varying models.

[quote="X5Sport"]
[quote="chrisn7"]
According to the WDS the X5 closed circuit current drain should be no more than 40 mA
[/quote]

US or UK version?  UK have an alarm system that is not fitted to the U.S. spec cars - and may not be fitted in Europe either.  That brings it up a little bit.

Richard
[/quote]

Fraid I can't answer that-you don't have to specify the VIN when using the WDS, unlike ETK and TIS.

For anyone who wants to do the current drain test:

http://www.meeknet.co.uk/e38/E38_Battery_Drain.htm

Same principle for E53 as E38

Good description.  If I may add one note of caution for those attempting the test.  Make sure you have an ammeter capable of handling at least 10A (or even more) in case the car awakens mid-test.  the only smoke you want is from the exhaust, not cooking electrical meters......

Richard

[quote="Smeeagain"]
my wife came back to a flat battery (third time in 3 months and only when she uses the car and i used it far more than she does ....)

Anyway, having forgotten all the instructions I gave her about jump starting she called the AA. He got her going but said that it needed a new battery because there was too much drain off it.

Now I wasnt there and she cant quite remember how much he said it was/should be draining. It is is a four year old Bosch silver S5 battery in an E53 3.0 Do Sport Auto 2004 - can someone tell me how much a good battery should be draining with the various permanent systems (he also didn't wait til it had gone to sleep as far as I can tell so presumably that would give him an 'incorrect' value)

Smee
[/quote]

Turns out the battery is fine and there is no drain. As I said in original post the AA guy didn't wait for the systems to shut down before declaring a drain. appreciate they have lots of cars that they are expected to know about but I think that is a basic error as I'd imagine the same principles apply to most modern cars these days
Smee

So short journeys killed it?

Richard

no not at all - she has a tendency to leave the lights on or not close the boot properly

New wife required maybe!

Perhaps time to trade in and get a newer model 

I had a flat battery issue with one of the E55 estates AA fitted a new battery didn't cure the issue AA called out again, again advised needs a new battery? When I pointed out they had not long (1 month) fitted one he couldn't give any reason other than short journeys as the alternator output was good.
Neither Mercedes or the AA could give an answer but one of my control engineers traced the problem to a soft diode in the voltage regulator. New regulator fitted no more problem I then read in the Sunday papers that AA operators were on commission for Battery and wiper sales, makes you think