Digital dash reads -- , loose HVAC control

[darklighter39]

hey,
I have a 92 STS and the dash will sometimes read -- on either side of the spedometer and tachometer. Also when this happened the Engine Coolant Temp reads -- in the system scanner. I've seen a couple other forums with this same problem. I have replaced the blower control module under the hood by the firewall and the fan. I can only think that the HVAC programmer behind the glovebox is fried. Has anyone tried looking in depth at this problem? Has anyone been able to fix this problem? Any input would be greatly appreciated.