yota-toy

My '86 turbo has no cable, my '88 non turbo uses a cable. If mileage is calculating it's not the pick-up. Like 68 said, check connections!

johngotts

The car has a speedo cable (very light brown off the top of the differential). I suppose this is more of a engine code driven option (KZ)being that there a so many different answers.
So I guess the question is (before I pull the cluster), since I do have a speedo cable, is the speedometer indicator mechanically or electonically driven by it? Don't forget, the odometer is working, and that is my source of confusion.

greattik

Just try with an electric pulse that comes to the speedo head, that the speedo control board interprets. It makes the odo motor turn, and generates a magnetic pulse which moves the needle.

johngotts

So, I detached the speedo cable at the differential, spun it by hand, and the speedo operates. I guess that means there's something in the differential (plastic gear?) that operates the cable. Anybody know of this?

johngotts

So, I answered my own question...
At the end of the speedo cable in the differential mount, is a removable shaft that has the plastic toothed gear on the end. It's easy to take out, one screw on the top of the differential that holds a retaining bracket for the gear, and out it slides. BTW, I also found that on the back of the instrument cluster, there is a mechanically resetable pawl for the OXS sensor that turns on every 30K miles. You just push the pawls forward and it resets the light. The pawls are accessible through a small square cut-out at the top of the cluster above the speedo head. It's labeled "OXS" by the cutout.