Cluster help again...

[Steven_Anderson]

Soo I did some research and I know that if the tach doesn't work it is most likely the Si board but here is my dilemma.
I just picked up an 88 vert. on the drive home from eugene the tach the OBC and everything else on the dash was working fine. but then the day after I started her up to go to school and the tach is not working and the OBC is not working, so I have an extra cluster with known working tach swapped it out and still no go on the tach. then I have an extra SI board that works and that did not help (tried on both clusters) Also the Speedo is off by a lot there is no way I, and the trucks on I-5 where going 100 at 3,000 RPM.

Please help me out its the only thing wrong with my vert and it is annoying.

[bzboardz]

you check the fuses?

[Steven_Anderson]

yeah but they look to be fine I will replace them any ways and try again.

[Steven_Anderson]

put in all new fuses for everything and still didn't work. speedo is also still off by a lot.
what else could it be?

[Steven_Anderson]

Also what size bulb does the interior light on a vert take?

[Steven_Anderson]

Any one? its not fun being paranoid that your speeding all the time.

[mr.vang]

is your mileage meter running? if the speedometer, ecometer, mileage meter and your stereo is not working then it have something to do with fuse 12. mine didn't work so i took out fuse 12 and scrape it on the cement. plug it back in and now it work like a charm.

check this for more fuse info

http://www.r3vlimited.com/board/showthread.php?t=60297

[Steven_Anderson]

the millage is working and the speedo is working it just says I'm going way faster then I am the only things not working are the tach and the obc. both were working fine yesterday morning. the PO said the tach stuck sometimes but it is not working at all now. in both my clusters.

[mr.vang]

have you check the speed sensor on the differential?

[bmwm42]

^+1 just what i was going to say

[Steven_Anderson]

Not yet what am I looking for when I check it? and where does the cluster pick up the RPM reading from the engine or is it also from the rear diff?
Thanks guys I have been away from E30's for a while.

[bmwm42]

try wiggling the back of the connections on the cluster and see if the fixes the issue might be a bad harness

[Steven_Anderson]

So I just went outside and checked the sensor at the diff and it looks to be in good shape the wires are not bad at all.

[Steven_Anderson]

If the harness is bad how big of a PITA is it to install a new one and I have never seen one for sale before have to find a parts car?

[bmwm42]

It really simple the replace the harness its attached to the steering column and all you do is unplug the old one and plug in the new one and I'm pretty sure someone on r3v has a parts car that can ship you one