Problem with Instrument Cluster

[Zreon]

Well I just purchased a 1989 Integra LS with 205k miles on it and I have a question about a problem with the instrument cluster. The Speedometer and the fuel gauge both work fine but the Tach,Temp, E-Brake Light only work some of the times. When I was driving it today, the oil light started flashing (Not solid) so I pulled over and checked it but seemed to be ok. When I got back in and turned the car on, the light was gone and all of the gauges were working again, but died about 30mins after that.

The tach is always at 0 and the temp gauge is always all the way up.. Normally I drive with the windows and sun-roof down, but today I was riding with the ac on and everything started to work, but died shortly after I opened the windows. So I think something is getting to hot in the dash so it causes those 3 things to malfunction.

If any of you could point me in the right direction on what could be causing this, please let me know.