Engine temperature gauge is inoperable?

There is just a blk/lb wire that goes from the sender to the cluster, so I would do a continuity test on that wire and if good replace the cluster with a rebuilt/used unit.

This guide will help with the test:

https://www.2carpros.com/articles/how-to-check-wiring

Here is the wiring diagrams for the coolant temperature sender so you can see how the system works. Check out the images (below). Please let us know what happens.