speedo odo stopped, now what?
 

There was a recent post on this topic but it went unresolved. Now I am in the same boat. After having the car up on jacks to work on the cooling system, the speedo and odo stopped working before the next test drive. Weird coincidence?!

I have read many posts on this but none that are definitive in this situation.

I believe that there is no cable involved as this is a late model (91 S2)
I have replaced the sensor in the transmission
I have cleaned the ground next to the sensor

Can anyone answer the following?

How do I test the wire, at the sensor, backwards (I have very limited electrical experience and hope this is a good place to learn some basics)?

Could it be the speedometer/odometer gauge itself? If so, can this be tested and confirmed instead of buying and replacing?

Could this be two problems in one? I read some posts saying it could be the infamous gear AND a speedo problem. However, since I have replaced the sensor I am hoping this is ruled out.

Thanks for any help as always,

any other guages out? check relays

No other guages out. Don't suppose there is a relay for just these two?! I will do some switching anyway just to rule it out.

It looks like I will be taking out the gauge after all. As I do this, does anyone know how I test the wiring while the gauge is out? I mean, I am sure there is a way to test resistance from the gauge back to the sensor in the transmission but which wire and how?! I have GOT to learn this electricity stuff some day!

Thanks!

One thing you can do that will potentially rule out some causes is attach the new speed sender to a drill, then have someone up front check to see if the speedometer moves. If it does, then you are missing a little gear in the tranny. If it doesn't, you have gauge/wire problems.

What a great idea! I will do this when I am checking my CV bolts!