Author Topic: speedometer & odometer troubles (Read 4309 times)

bryan@cedainc.net · « **on:** September 15, 2011, 04:07:26 PM »

Speedo & odo were not working at all but all other gauges, lights, etc. work in the cluster. So, I replaced the speed sensor in the differential & they both started working....sort of. When I accelerate, speedo stays at 0 but when I let up on the gas, it jumps up to the approximate speed & bounces up-and-down. It never rests on one place. I was careful on the installation of the sensor, which is pretty much a no-brainer: 2 small bolts & plug wire.

Is it possible I simply positioned the sensor incorrectly or has anyone had this problem & were able to resolve it? Any feedback will be appreciated.

DesktopDave · « **Reply #1 on:** September 15, 2011, 06:21:40 PM »

I had a similar problem, but it was with the wiring over the diff. I had to cut & splice another pigtail in to solve the trouble.

I'd be very tempted to take the cluster apart & see if it all looks OK.

bryan@cedainc.net · « **Reply #2 on:** September 19, 2011, 07:38:50 PM »

Yeah, good idea...alot cheaper than pulling the cluster. Thanks

DesktopDave · « **Reply #3 on:** September 19, 2011, 08:07:11 PM »

I found a board in an eta that had a single burned trace on the main circuit board. Not sure what happened there, but it was easy to diagnose. You're inspiring me to take a crack at repairing it & see if it gets to working again.

A bouncing set of gauges might also be from bad capacitors on the board. They damp out signal transients. Weak caps are infamous on later e34 dashboards. Check to see if any are visibly leaking or bulged.