Gauge Cluster Issues.

[noE30]

I know that its a common issue for the odometer gears to go out in our cars but what about the speedometer? My speedometer is no longer working correctly, it only works like 50% of the time. Ill be cruising along and notice the needle fall to 0mph and because the speedo isnt reading any speed its also not spinning the odometer.
When this first happened I figured that it was the odo gears but I havent read anything about the speedo going out too. So is there a speedo gear that I need to replace?
Thanks

[Gerta]

Hey ... I'm a total noob, but I've tracked a similar problem back to the SI board batteries. Tons of info on here about that so I won't belabour it. Does everything else work on the cluster?

[noE30]

so far yes everything else works beside speedo, odo, and the tripmeter.
And yes I have read some info about the SI batteries, might have to do some more research on those though.

[rThor432]

Check the plug and wiring to your vehicle speed sensor, located in the differential cover. I see issues there all the time.

It isnt your SI batteries, other stuff would be acting funky.

[noE30]

Is there a connector inside the cluster for the sensor? Because I notice that when it stops working I can tap on the top of the dash and center of the steering wheel and the speedo will start to work for awhile.
Do you think something might be disconnected inside the cluster?

[ZM Blue Devil]

have you taken apart your cluster? new issue or always been that way?

[noE30]

I have never taken apart the cluster. This issue just started probably 3 maybe 4 weeks ago.

[rThor432]

I notice that when it stops working I can tap on the top of the dash and center of the steering wheel and the speedo will start to work for awhile.

Sounds like a bad solder joint.

[noE30]

well the car will be going into "storage" for the winter in the next month or so. And I will already be doing some work to it so I guess ill just have to pull the cluster as well.

Any other ideas or things I should look for?

[Gruelius]

dry solder joins and burn marks i guess.