Newbie Need help with 2009 bmw 528xi no power at all
 

Allow me to introduce myself my name is Walter I live in Sacramento,ca i own a little man repair shop for my bmws currently own 06 bmw 530i 00 bmw m5 imola red 95 bmw 328i (project build) 97 bmw m3 hellrot red.. From time to time i do repair jobs on friends and fam. Just yesterday i took inn a 2009 bmw 528xi 35k miles this car from what i was told was a Newyork car. It suffered flood damage and seems like it was severely damaged. IT does not have any power at all to dash/gauges etc etc. the only power it seems to have is to the motion sensor in the rear view mirror. i have made sure the battery is charged up. I know some of you might say, car is not worth... too much work. etc etc.. thats not the answer im looking for.. My friend just spent that amount of money not knowing it was flood damage. So now it has to be fixed. the car cant just be sold or thrown away. Point being. i need to know if anyone can help me out by pin pointing the modules or sensors that control the main power. also relays in the rear trunk space that will cause the car to have no power at all. also the doors dont seem to be opening up. Maybe imobilizer? any help would be great. and thanks in advance.

You have a real problem in your hands my friend . What I can tell you is to google www.bmwoem.com . This page has the parts diagram of the whole car . And good luck

i was the shop yesterday and overheard someone talking to a tech about their vehicle getting hit and having no power at all..to anything, period.

the tech said there is a breaker on the battery cable (don't know what kind of bmw he had) that will flip when the system detects a heavy impact to the rear, or a short in the system.... it apparently is to prevent fires.

however it of course does not cut off a redundant circuit to bmw assist which could explain, and i emphasize could, why the mirror has power. (i am assuming the mirror may have a mic or assist button on that model year but i dont know)

I would check that battery circuit to the main bus's on the car. I'd check for voltage everywhere you can with a meter and eliminate things one by one.

there is a chance some main relays and or fuses blew from the water shorting the system, BEFORE the battery may have cutout, since this was not an impact or quick short of the main system, but rather a short in perhaps an individual bus.

thats what i can think of at the moment.

You might check the laws in the state it was sold in for selling a car with known flood damage and selling it as a clear title. The buyer might have recourse, especially if it was through a dealer.