BMW E60 530d dashboard failure

[omglol]

Hi!

I have a strange problem with BMW E60 2003 dashboard. The customer claims the battery went flat (he forgot the ignition ON) and then tried to jump-start the vehicle with a 50Ah battery. This didn't work (speedo gauges were just playing, no crank at all ...), so he called his friend and they successfully jump-started the BMW via 100Ah battery. Everything was working OK, including dash. Next morning he put ignition ON and the dash was just dead ... absolutely NOTHING works on dash. I checked the 7,5A fuse (position 13 if I remember) and it is ON ... also I checked the dash plug for +12V and I there is +12V on ignition ON ...

What could be the problem? Does anyone have wiring diagram? Thanks!

[diga1]

try to test mosfet in cluster unsolder it and try it on bench it might be stuck

[omglol]

Which one do you mean? There are only 2 voltage regulators (LM2595S). Photos:

http://dl.dropbox.com/u/2523271/29102011222.jpg
http://dl.dropbox.com/u/2523271/29102011223.jpg

[diga1]

first check if they vork properly then go further

[omglol]

Hmm ... don't have actual idea how to check this one .... Did you have any case when this voltage regulators were the problem?

[tachonow]

Maybe power shocks caused dump corrupt.

[diga1]

few times i ha a problem vhen client was canging battery and ignition was on a few computers died in car, for example two weeks ago client was canging batery on vw caddy 2006 and ign was on and both dor modules died and came to me and i tested dor module and saw that mosfet didnt let power trought so i replaced them and evrything worked. so try to connect plate of cluster in to a car give ignition and take multimeter and look if there is voltage coming out of that regulators if is, go further by the line and check vhere voltage dissapears, my opinion if it was dump there shuld be some life in cluster some lights wuld go on or something, but you can check that too.

[nimnul]

Check MCU FUJITSU/MB90F394H. Pin 37 is ground. he might burn out.

[drpeter]

Check MCU FUJITSU/MB90F394H. Pin 37 is ground. he might burn out.

I think the cause is because of a earlier mileage correction.
Someone soldered the M35080 eprom, maybe without ESD protection. Chip was weak and overcurrent killed him. Check eeprom content.

[omglol]

Solved. When I tried to take measurements on voltage regulators, the dash magically begin to work perfectly OK. I then resoldered most components on PCB and it works normally now. Thanks for help!