Intermittent speedo 97 XLT

[David in NC]

I've searched this and found information, but have been confused by answers for wrong model years. I even added to the confusion by posting that my problem was with a 99. We have (had) two Xs, a 97 and a 99.

Our problem is the speedo on our 97 occasionally drops back to zero while running down the road. It may go days without a problem. It may bounce a few times then be fine for a while. And it may quit working at all until the next time we go out.

My son says that the odo stops when the speedo stops, but the cruise works all the time.

Does this sound like a cluster problem or a cluster wiring problem?
Does the same speed sensor run the speedo. odo, and cruise?
Where should we look?
What is the fix?

Thanks,

David

 

[patrick112390]

I've searched this and found information, but have been confused by answers for wrong model years. I even added to the confusion by posting that my problem was with a 99. We have (had) two Xs, a 97 and a 99.

Our problem is the speedo on our 97 occasionally drops back to zero while running down the road. It may go days without a problem. It may bounce a few times then be fine for a while. And it may quit working at all until the next time we go out.

My son says that the odo stops when the speedo stops, but the cruise works all the time.

Does this sound like a cluster problem or a cluster wiring problem?
Does the same speed sensor run the speedo. odo, and cruise?
Where should we look?
What is the fix?

Thanks,

David

mine does the same thing, replaced vss (vehicle speed sensor) to no avail. here is a vid i took of the event-sometimes it will just o straight to zero ....tell me if this is what it looks like so we can solve this together

http://www.youtube.com/watch?v=nGzg6R_J5N0

EDIT: i am pretty sure its the cluster, and not a computer issue, because i can watch my speed on my SCT tuner/moniter even when its at 0......

 

[David in NC]

That looks like it. I'd hate to change out the cluster to find it is some other problem.

 

[Cobraguy]

I don't have a diagram for a 97, but I do for a 96 and they SHOULD be the same as I don't believe they changed speed sensor strategies until 98.

The VSS signal is distributed through a splice (S169) to the PCM in one direction, then to a second splice (168) in the other. The second splice goes in two directions also...one to the cruise amplifier and the other to yet another splice (S247). That splice branches off in at least 4 directions...to your instrument cluster, message center, GEM, overhead console, etc. So, it is entirely possible to lose the signal to your instrument cluster from this splice and yet have everything else work. This problem sounds like you have either a bad cluster, or a bad wire to the cluster from that last splice if everything else works. What you might do is use a frequency meter and check the vss signal at the cluster (with the connector disconnected) and see if it truly dies or if it's a good signal.