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View Full Version : Capacitors in a '95 Cluster...dif than E34.net



Aaron Bakos
01-09-2005, 12:21 PM
'95 525i 5spd-

Weirdness going on...was away for ~10 days for the holidays, came back and the battery didn't have enough to crank so I grabber the jumper cables. The next day after driving for a while the speedo started jumping all over the place, eventually settles it at 2x my actual speed. The OBC still reads properly, but the speedo is reading double and the odometer is accumulating at 2x as well. When the car is cold there is no problem, after everything warms up the speedo will jump around for a minute or so, then settle in at 2x.

Read the writeup on Bruno's site, popped the cluster out, and the circuit board looks nothing like the writeup. At some point they went to a double-sided board and it's put on with melted standoffs. I drilled out the standoffs to get at the back of the board and I found 4 capacitors, haven't replaced them yet. The small screws they give you with a new hard drive are the perfect size to thread into the standoffs to secure the board again :D

Just wondering if anyone has any thoughts (or a used '95 cluster :) ). I've got a bunch of pics if anyone wants to see.

I just think it's weird that the OBC would read the correct speed, makes me think it's not the speed sensor. Also, since it only happens when the car is warmed up, it definitely makes me think it's something electronic. Since the OBC is reading the right speed, I'm inclined to think it's somewhere in the cluster...but I honestly have no idea.

If anyone has any ideas, I'd certainly appreciate it!

Cheers-

Aaron Bakos
01-11-2005, 07:05 PM
Nobody? Any ideas?

bimmerd00d
01-11-2005, 08:10 PM
i would remove that battery cable for a day. see if you have any luck doing that.

Aaron Bakos
01-11-2005, 08:31 PM
Tried it...then made sure I didn't bounce the connection when I hooked it back up.

I guess I'll pull the speed sensor and look for any damage, then maybe swap out the capacitors on the board and see what happens.

It's just really weird that it settles in at exactly double, and only after the car is warmed up.

Javier
01-11-2005, 08:48 PM
take a look to this page, OBC is supposed to calibrate the odometer (see *1), I have never tried, but!!!

http://home.iae.nl/users/bts/obc.htm

In any case, if there is comunication that permits the instrument panel to calibrate, may be loosing the link will set the system to adefault value, causing this weird behavior. Just guessing.

Javier