How do I test my instrument cluster?

See the trace from the IVR leading off to the right to the two gauge studs? Goes in that one

Also, loosen/ tighten the gauge stud nuts, or better yet replace them. That will "scrub" corrosion off the trace

Check in the thread I posted about PC board repair that the pins at the connectors are in good shape AND THAT THE contacts of the IVR socket are making good connection

Replace the IVR with a solid state unit