78F350

I'm working on a 1993 Del Sol that has been sitting for a few years. The speedometer does not work, but everything else does. The odometer and trip mileage work fine. I just pulled apart the cluster and re-flowed the solder on the speedometer module. Still nothing. I swapped another cluster in and still had the same problem. Now I am guessing that both old clusters have a bad speedometer. Is there anything I am missing, anything else to check? I see plenty on eBay for ~$100, but I'd hate to put another one in and still have the problem.
I have been through this: VSS - Vehicle Speed Sensor Troubleshoot, Repair, Replace - How To. and several old threads here.

Thanks

78F350

Still searching, I came across this:
https://honda-tech.com/forums/honda-.../#post25576684

I just checked pin B7 on the cluster harness for the signal (+5V) and it was good, between 5v and 6v while I had the front of the car on jack stands running in gear. If B7 is the only VSS input to the cluster, then I think it must be a case of both my original speedometer and the one I swapped in, being bad.

bodiby

Check the ground while pulled apart.

mk378

If odometer works the problem is almost certainly in the speedometer head. Take it out of the cluster and check / replace the capacitors on the circuit board like you would in an ECU. Blow on the needle to check that it is mechanically free to move. It should be able to go upscale and spring back to zero.

The sensor signal pulses between approximately zero and approximately 12 volts. You can see this if you lift one wheel off the ground and turn it slowly by hand (key on, engine not running, transmission in neutral, other wheel not turning).

78F350

Thx for replies. I went ahead and bought another used one form eBay, should be here in a couple days. Meanwhile, tomorrow I'll take apart the two I have to check capacitors and see if I can trace the path of the signal to the speedo.