Speedometer Not Working?

[Quinthirty]

Hi,

I already checked fuse and the cluster connections, and it seems that there is some connection I'm missing in the speedometer itself as speed isn't being recorded. Anyone knows what to check on what the connections on the PCB of the speedometer are so I could check if they're connected or not? What about connection to tranny?

Pulled down cluster as the odometer wasn't working & thought that the gears were broken. Only found them to be dislodged and put it back together.

This is supposedly a "new" speedo as the PO replaced it, and turned over the old one to me too.

[Gregs///M]

Does the speedo work or is both speedo and odo not work? Start with replacing fuse 10, 12, and 21 with 7.5A. Also check your connector at the rear differential. Its the speed sensor and can be exposed to the elements and generate oxidation on the copper. Clean it up with a file or wire brush and re-secure.

[Quinthirty]

Thanks, Greg. I'll keep you posted.

Yes, both odometer and speedo are not working. Before that, the speedo was working and the odo stopped. I was hoping that when I fixed the dislodged gear, it would get back to normal, but it didn't.

[Gregs///M]

Yup, if both do not work, the cluster is either not getting signal or not getting power. Use those suggestions in my previous post.

[E30NJ]

replace the speed sensor in the back of the diff for the speedometer. odometer gears most likely broke. not horribly hard to fix but you need to be very careful and take your time doing it.

[Quinthirty]

Thank you. I will work on the speedo connections at the differential over the weekend.

@E30NJ. I already looked at the gears. They're intact, just dislodged as its a new speedo installed by the PO.

[Quinthirty]

What is wrong if you put the ignition at position 1 and the speedometer goes all the way to the end (max speed) and stays there? My hunch tells me that polarity is reversed?

[jlevie]

What is wrong if you put the ignition at position 1 and the speedometer goes all the way to the end (max speed) and stays there? My hunch tells me that polarity is reversed?

That suggests a failure in the speedometer electronics to me.

[Quinthirty]

Shorted a circuit along the pin connections, but it was good that the guy who helped me was able to fix it. Took him 10 min to fix and test it.