93 k1500 temp guage

The temperature guage on my k1500 stay right around the 100º mark. I replaced the sending unit...didn't help. I unplugged the sending unit, and turned on the truck to see if the guage was getting power. It cycled to hot and back to cold just like it does with the sending unit connected. So, I assume it has a power source other than the sending unit itself. It might still be the guage itself. Before I go tracing wires or replacing the guage, anyone got any ideas? Thanks everyone-

I would make sure all the ground wires are solid and not corroded. I had a similar situation when I changed my thermostat I sandblasted the water neck and cleaned off the studs/bolts of rust then lo and behold my thermostat worked after that!

Did you change the right one? There are two sending units for temp, one for the guage and one for the computer.

I cleaned the ground...no luck. I changed the sending unit on top, front of the block. The one with two wires coming out of it (Black and yellow I believe) with an oval shaped connecting plug on top of it.