what do you mean? did they stop working, work now and then, or what is working and what not? if everthing is dead and the truck runs ok, then ckeck the fuses, but im not sure at all it could be PCM related.
There is no fuse just for the speedometer. If the speedometer is not working, you may have a problem in the dash gauges cluster, or a vehicle speed sensor problem.
my 1998 doge ram van, all my gauges are not working
You have to access the gauges by removing the cover. Unless you know what you are doing, you can mess up a lot of things working on the dash.
Cluster removal link below: http://www.youtube.com/watch?v=6jXiwgm3bPg
It could, along with the gauges themself and dozens of other causes. A scan tool capable of communication with the body computer and cluster is required to diagnose.
Your speedometer may have failed, or the speedometer cable that connects to the transmission, or the plastic gear in the transmission may be broken.
I had the same problem with my 1998 Dodge Ram 1500. I reseated the instrument cluster and it started working. The whole thing took me 15 minutes and I am not a mechanic. I believe that I removed three screws to enable me to remove the plastic which covers the instrument cluster. I can't remember how many screws hold the cluster down but once you remove them pull the cluster out. It is simply plugged in, and those connections are your problem.
My dash lights went out and the cause was a bad alternator. new alternator fixed the problem
It will have to be removed and sent off for repairs.
No. The spark plug wires have nothing to do with the illumination of dash gauges. Check your fuse box for blown fuses. A blown fuse that corresponds to the instrument cluster will cause that.
These vans are bad at the instrument clusters "locking up" and shutting down the "bus", the communication system for the computers on the van. The pins soldered on the back of the instrument cluster can become loose after time and vibration . Under close examination you can see the joints are not solid . Resolder (heat the joints with solder iron).
Cluster Computing was created in 1998.