Cluster and electrical problem

So my 2004 gmc Yukon Denali cluster doesn’t work. I checked all the fuses, check relays speedometer is stuck at 32 mph with vehicle on or off. When I try to switch over to my dims, my light shut off completely, and the cluster doesn’t show that my brights are ever on only when the actual light switch is off. None of the gauges work by the way I should include.

The speedometer error is likely a gauge stepper motor issue, very common. Has the cluster ever been rebuilt, meaning stepper motor replacement?

There are several circuits that go to the cluster, but the main power fuse is in the underhood electrical center:



Check that circuit/fuse to make sure it's good.

Also, there is a problematic ground on the driver's side body mount, just behind the left front tire (next to the frame under the driver's door hinge area). There are two bolts and 2 or 3 wires grounded there; remove the wires and clean those grounds. One of those grounds (Ground Zone 18) is the IPC ground #2. There is also a ground up under the dash cap on the passenger side, less problematic. See the attached grounds diagram from the GM Upfitters Guide.

Lastly, you can pull the cluster (easy, many YouTubes on how) and check the powers and grounds per the attached pinout graphic. B11 is the main B+, but also verify the grounds.

Let us know what your troubleshooting shows.

Lastly,

For sure and thank you for the right direction. I’ll get back to you soon as I can with the results.

For sure and thank you for the right direction. I’ll get back to you soon as I can with the results. But I also don’t know if it’s ever been rebuilt the cluster I mean. . I just recently purchased the vehicle. I do know the previous owner had a shut off switch on the negative sided of the battery because over a few hours to a few days, something in the vehicle would drain the battery somewhere

the accessory fuse can also affect the cluster, check that one as well, there may be 2 accessory fuses 1 is for sure in the drivers side dash fuse panel (end cap) may be another in the main fuse box under the hood