93 sse a couple different problems

ok i have a 93 bonneville sse 3800 with somewhere above 186k on it. i have a couple of different problems with it. the first is that the dash only seems to have power when it wants to. it may come on as soon as i start the car or it may not come on all day. when it does come on, it will work just fine until i shut the ignition off. when it works, everything works just the way it should. the heads up display works whether the dash is on or not, however, i have discovered that if the dash is not working and i have the headlights on, the heads up display speed goes up and down and never shows the correct speed. if the headlights are off or the dash is working, the hud speed is right on the money and constant. also i cant get the hud position to adjust. the other problem which i suspect to be unrelated is with the electronic climate control. since i have owned the car, i have only seen the display twice and just momentarily at that. the rest of the time it only shows three dashes on the ecc display. it blows on about a medium-low speed through the defrost vents and the temperature is constant at whatever speed you can manage to set it on when you manage to catch it working for a minute. i've done a lot of wrench turning in my time but however this is kinda like outta my area. i've read through the posts back to sometime in 2008 and havent seen anything quite like these issues. thanks in advance for any advice

If you have a digital dash more than likely the cluster is bad as is the hvac display ,both were common problems. Poor soldered connections in the circuitry were the issue.

Over time the Pins in the Multi Connector for the cluster can become corroded and or the pins loose their tension and need to be bent back into their proper place...

For the Digital displays, its possible to have a bad connection on the board, bad ballast iirc or simply a failing unit...

thanks, first chance i get, i'll pull the cluster and see what i can figure out on the connector. unfortunately, that may be a couple of weeks or more. eighty and ninety hour work weeks keep my time rather occupied!!