Okay this is really weird. On my 93 my instrument cluster was acting funny, and I thought that it was going out as I've had one do that before. The speedometer will only display 0 for about 30 mins, after 30 mins the speedo displays the mph but it fluctuates between 5 miles under or over the actual speed. The other issue is while the speedo is only displaying 0 after about 10 mins the service engine light will come on, but will go off when the speedo starts displaying the mph. Additionally when its doing this the temperature display will also fluctuate from 200 degrees to 230 degrees back down to 210 and so forth.....

So I have had my original cluster sent off to be fixed, and I am about ready to install it... do you all think its the cluster causing the problems or something else?

I would start with the cluster.

With all those divergent issuesm, it is either the cluster or the plug to the cluster.

Oh, long time no see! hope all is well!

doing good Bogus, I peek in every now and again.... just working on the little annoying things that need repairing.... let's see, I've had the power window switch driver's side replaced, the exhaust manifold (driver's side) replaced, window guide passenger's side replaced, left side headlight motor, and those darn pins in the steering column.... gotta do the weatherstripping soon and maybe the stereo upgrade.... after that, then the engine...

So this same problem has happened on two clusters? If so I'd check grounds and connections first.

Quote:

yeah... however I have over 260k on the car.... but I will check the grounds when I install the repaired cluster...

UPDATE: got the original cluster back, put it in... still not registering the speed... called my mechanic who looked up some stuff and informed me that the schematics are complex and that the signal for the speedometer go through at least 4 modules. Whatever the problem it will have to be scoped, so I will drop it off next week to run the diagnostics...

Strange, my manual says it goes from the VSS to the ECM then to the CCM then to the cluster.

It feeds the Selective Ride Control and SCV on the stereo and the cruise function off of the VSS.

The big questions, does the SCV and cruise work?

Nope, the cruise control has not worked in years....I don't have selective ride control...

And the SCV?

I am wondering if the VSS is bad... as is Jeff...

It does go through a lot, but, the parts it goes through are rather reliable. The ECM needs vehicle speed to make the cruise work... in addition to tach signal.

The CCM uses it for the SVC - this feature adjusts volume with speed.