Help!!!
1998 2500 V10 4x4:
I'm in the Wildwood, Florida area. I have a problem with my instrument cluster guages. Dash lights work, but none of the guages work (battery, temperature, tachometer, speedometer, oil or fuel). Throwing codes 920, 921 and 999. The words "no bus" DO NOT appear in the display. The overhead display works and shows compass and temp as it should but no codes. I bought a second (used) instrument cluster, that did not fix the problem. Truck starts runs and drives fine, every time. Truck does not die while running and idles fine. Ive check fuses both under the hood and on the side of the dash, they are all good.. Hope someone here can help figure this out and/or suggest a shop that can fix it without me having to sell the farm to pay for it. I have minimal to no experience in electronic diagnostic to figure this out. If additional info is needed please let me know. Thanks

 

Does your check gauges lite come on??

 

920: The cluster is not receiving a vehicle speed message from the PCM.
921: The cluster is not receiving a distance pulse message from the PCM.

From what I understand that means the CCD bus is working (as opposed to "no bus") but the cluster doesn't receive any data from the PCM. If the ABS and airbag lights come on and go off during start those modules can talk to the cluster but the PCM can't.

 

If you're referring to when I go through the instrument cluster test by holding down the tripometor button. The word "check" shows in the mileage window. It then proceeds with the test of the the cluster. Codes 920 911 and 999 show up and the test pauses until I press the button again, the test continues, the guages sweep across the dials. They then return to their resting position. Test ends at that point. During the test I believe, all the indicator lights operate properly.

 

With the engine running, and your gauges not working, is the check gauges lite on?

Pretty much everything on the cluster is driven by the data bus. Do you have a scanner? Will it communicate with the PCM?

 

Based on the description the cluster itself is working. Most lights in the cluster are controlled via the CCD bus (a few are conventionally switched on/off) but not all are controlled by the PCM. ABS and airbag modules talk to the cluster as well. So looking at what the lights do during startup will give you some indication of what's going on. If ABS and airbag lights work normally that means other modules can communicate with the cluster. If lights like check engine, check gauges stay off or on the PCM can not communicate with the cluster. Maybe make a short video and post it here.

A regular parts store scanner talks to the PCM on the SCI bus and will tell you if the PCM is totally unresponsive but given that the truck runs that's probably not the case. To talk to the PCM (or ABS, airbag) on the CCD bus a "shop level" tool would be required, unfortunately.

 

With the key in the on position the lights that are on are SECURITY, ABS, FUEL,, BRAKE AND SEAT BELT.

When the truck is first started, the security, fuel and seat belt lights remain on.

When driving, the ABS, fuel seat belt and break lights are on.

Also, not sure if this is related but my interior lights are not working, neither the dome light nor the overhead console lights. All fuses have been checked are tested ok.
Sorry but I have no idea how to post pictures or video

 

Hmm this sounds like the cluster is not receiving messages but it's weird that it doesn't show "no bus". I assume the ABS is functional otherwise. Do you know anybody with a high end diag tool ? It would really help to see who can communicate on the CCD bus and who can't.

 

Unfortunately I do not know anyone with a diagnostic tool.. this is really puzzling me. I got a hold of another (used) cluster. When I installed it, it showed "no bus" 920 921 and 999. It also showed the blue high beam indicator. This stayed on whether my high or low beam were on. It still showed even when my head lights were off. Not sure if that has any bearing on my issue

 

What year truck was the other cluster out of?