1988 trans am GTA with 140 speedo.
My odometer quit working because of the plastic gear giving out like normal so I replaced the gear, put everything back in and now my speedometer and my odometer isn't working. What's the first thing I need to check? Was super simple swapping the new gear in so I don't think that is the issue. All other gauges are functioning except this one. where to i check first?

 

Unhook the cable down at the gear and spin the end of the cable with a drill, see if the speedometer does work. Maybe a broken cable if it doesn't. Was the new gear the same color as the old one?

 

Is there a cable? I thought after 86 the firebird was electronic?
The gear was not the same color. But im sure the original one was white at one time. My car only has 84,000 miles.
I got the gear from odometergears.

 

The motor may have burned out if the gear was stuck to the shaft and teeth didn't break. Happened to one of my 89s

 

Teeth did break and speedo was still working after that I just noticed the odometer wasn't spinning. Now after the gear replaced neither work

 

Took it back out. Looks like all teeth are good. I can spin the screw on the motor with my finger and odometer and trip move. I'm guessing I need to replace the board to the motor because I'd the motor fails then the speedometer should still work right? If they both aren't working than that makes me think board. I don't see any burn marks on the board though

 

Is there a way to test the motor and circuit board to rule them out?

 

Bump! Still needing to figure out the issue

 

If You need a temporary Speedo Remember your phone has an app you can download. If you're afraid of tickets while you fix it.

App search: Speedometer GPS based but it works

 

In my 1984 T/A - the speedometer works fine. The Odometer works fine. The tripmeter works fine. However, I cannot reset the tripmeter to 0. Push the shaft in&/or turn the **** - not working. Fix?