Troubleshooting battery drain
 

Hello members
This week all of a sudden my 2006 3.0 X5 alarm goes off suddenly in the garage. I run to the garage and see one headlight on and the other off and it slowly fading away and the alarm sound fading away as well. It seemed like the battery going dead and sure enough could not unlock the car with the remote.

Long story short the battery was less than 2 years old and got it tested and it came back good. Was told to test the alternator and tested at jump points I get 14.3V so alternator seems good.

Reading through the forums I have red the FSR being the drain culprit but I can't seem to find any symptoms of a bad FSR or I don't understand what the symptoms are with one of them being 'huffing'. Don't want to replace the FSR is its not bad.

Any help or further troubleshooting steps would be appreciated.

Thanks

there are many posts on the battery issues...

have the battery tested at the place you bought it from, on their bench - they test for dead or bad cell, something you can't identify with a multimeter... if their machine says it is bad, they should replace it, as it is probably under battery warranty...

test the alternator while you are driving - unlock the OBC functions, and read the voltage as you drive... testing the alternator output at the jump point will not yield the desired results... again, there are plenty of posts which talk about the OBC unlocks, and the desired voltage range...

do it and let us know, what your results are... a bad brush or a voltage regulator on the alternator will result in inproper undercharging (or overcharging ) of the battery, so those two things are intertwined - you need good alternator and a good battery, if bad alternator is killing a good battery, you still need a good battery to test and catch a bad alternator... so.. start with the battery...

Terminator X5,
Thank you for your reply and sorry for not being clear that I did remove the battery and took it to the retailer and they tested it after charging the battery and they said it was good.

I also did unlock my cluster it and it displays a voltage of 12.0-12.1V which is little off than the multimeter at battery terminals which showed 12.25V

Thanks

was 12.0 -12.1 voltage while the engine was off? or, the engine was running? if the engine is running, the voltage should be above 12VDC nominal, in order to charge the 12V battery... if that is the reading you are gettng, your regulator might be going bad...
if the running voltage is good (13-14V), then we should start looking for current leak - could be anywhere in the car... with a leak, the car will run fine, but will have problems restarting...

Sorry for not being clear again. Here are the readings.

Engine not running reading
Mutlimeter - 12.25 - 12.45V
OBC - 12.0 -12.1 V

Engine running
Multimeter - 14.3V
OBC - Not tested yet.


And to continue. The only non-factory accessory I have in the car is a DICE Silverline. So last night I disconnected the DICE Silverline and and measured the battery voltage with a multimeter (engine not running) and it was 12.45V and this morning woke and took another reading again with engine not running and it was 12.25V. The drop of .20V overnight seems a little too much to menwhich like you said I might have troubles restarting the car if I don't drive it for a day or two.

Thanks

was the car alarmed overnight? voltage and amperage are link to each other but the amperage is harder to measure, as you need to "splice" the instrument into the line in serial connection, while voltage can be read in parallel... if the car is parked overnight and is not alaermed, there will be a very nominal voltage drop in the battery, occuring naturally... very negligible, unless the car is parked like that for several months...
the alarm will drain the battery much faster, but should not do so in a couple of days - some members have reported car being parked for a couple of weeks at airport lots with no problems... my own cars would last without restarting the engine for about a week, at the most...

give it some more of your time, but, if the problem is not coming back relatively soon (within a week or two), just "write-it-off" as a fluke and move on... if it comes back - then we will need to dig deeper and commit more resources to it...

Just a few months had the sitting in the garage for at least 3 weeks as I was out of town and the X started with no issues and I am one of those people that lock and arm the alarm even in the garage :)

Yes I also did the amperage test but it was tricky to work out the test since I have to have the trunk open to create a serial connection and it showed a draw of 4.5 Amps which is probably due to all the interior lights on with the trunk open. If I close the trunk it gets tricky to read the multimeter display as I have tinted windows on the X. Also read that I need to wait for 15-20 for the car to go into sleep mode which I would assume only happens with all doors/trunk closed.

car will go to sleep after 16 minutes even with the doors and/or trunk lid open...

Thanks TerminatorX that gives me something to work with now.