2003 ZX2 Speedometer Problem

I have a question that I hope someone can answer. My 2003 ZX2's Speedometer has been malfunctioning. It will read correctly for about two to three minutes and then peg to 125. This problem occurs when it is very hot outside, and seems to go away if I drive for an extended period of time. Does anyone know what the problem is and how I can fix it? Thanks for you time.

Sounds like you might have a short.
Pull the gauge cluster out. You'll need a T10 and T15 torx driver.
Make sure all the connections are good. If that doesn't do the trick a new gauge cluster is pretty cheap at the boneyard.