HVAC Programmer issue?

I have been helping my father 'try' to repair my '95 Pontiac Bonneville for the last several months. We are having an issue with the air conditioning. Our problem started last October when I went to Wal-Mart to have the battery replaced (simple enough, right?). After they replaced the battery, I noticed the 'exterior temp' on the electronic climate control was flashing for a minute or so before locking on to an exterior temperature.

I went through the winter and everything was fine minus the flashing lights on the climate control. This spring when I decided to start running the air conditioning, it was blowing hot air. I took it to have the a/c serviced... found there was a leak in the line and they replaced it and it was blowing cold air. I went home and left the car overnight and when I got in the next morning, it was back to blowing hot air. I proceeded to take it to a local Pontiac dealership and they told me it was the HVAC Programmer that needed to be replaced to the tune of $1,000. I declined their offer to fix it knowing that my father would probably be able to figure it out.

We ordered a new HVAC Programmer off Ebay.. same part number, everything for a lot less. We installed it and are still having the same problems. We returned the Programmer and had a new one sent (in case the original was defective) and still have had no luck. We have checked all fuses and they are fine.

Is this an interior sensor issue? and exterior sensor issue? In the manual, it says "When you start your vehicle and the EXT TEMP display flashes for some time, the system may need repair. See your Pontiac dealer. NO KIDDING!

Any help would be greatly appreciated!!!

I think there is a reset that has to be done if you remove the battery power. Check on the net or maybe someone here might know.

Please refer to this thread http://www.automotiveforums.com/vbulletin/showthread.php?t=298431&highlight=climate. Sounds like an Air Mix problem

Please refer to this thread http://www.automotiveforums.com/vbulletin/showthread.php?t=298431&highlight=climate. Sounds like an Air Mix problem

Thanks for showing me that. I talked to the dealer yesterday and that is exactly the problem. The temperature control door is not opening/closing properly. They told me it was a 'nightmare' to replace as they have to rip out the dash. I am still waiting on a quote from them as we speak.

Keep looking through the threads there are several for this issue. I read some that describe "alternate methods" to replacing the bad unit that don't involve removing the dash. Good luck