If it was working before you pulled it out, then likely you need to look at what you did again. Not a likely coincidence that it died while you changed light bulbs, but anything is possible.

Might be obvious here, but if you have the fan OFF, the AC and Recirculation will NOT work.

 

Thanks for the response. Blower was on and still no ac or recirculation or heat. Looking like a component level problem in the control module. That's beyond my pay grade. I am going to get an OEM used module. Does anyone know if it will need to be calibrated after installing it?

 

Calibration is required after disconnect!

video:

 

I've disconnected my HVAC control MANY times for various reasons thru my 16 years of ownership. NEVER calibrated and always functioned properly.

 

Yep me too, on more than one H3. When you start it back up, lights flash, you can hear actuators open and close blend doors, then all is good.

 

Just re-read HUMMERZ post and the re-calibration instructions say: "When Replacing An Air Temperature Control Assembly" NOT 'Disconnecting' as he posted. 'Replacing' seems to be the key word.

 

My OEM assembly line installed, HVAC control assembly works perfect!
2 things to consider, and understand the meaning of "REPLACING":
1-OP has an issue after disconnect, was the key in the ignition & in the on position? WHY NOT TRY TO RE-CALIBRATE first?
2-OP asked if installing another HVAC control assembly, would it require calibration?
3-Removing the HVAC control assembly to replace bulbs requires disconnect! Replacing definition is noted below:

 

You used the word/term "disconnect."

 

I'm thinking if you just R&R your original controller no re-calibration is necessary, as it retains calibration. Only if a NEW controller is installed THEN you need to re-calibrate.

 

B+

Battery voltage disconnect can cause an issue with many different modules throughout all vehicle manufacturers. Requiring re-calibration, reprogram, or reset. I've never disconnected my HVAC controller, yet anytime my drivers door master switch is disconnected/losing B+, it became inoperative until reset(capacitive discharge). The factory radio requires reprogram after disconnect from B+. The HVAC may maintain residual voltage when disconnected, yet when not operating properly after reconnect, try to re-calibrate first.