It’s been storming here and when I go to defrost my windows, I noticed my AC button would not turn on when I have the temp knob in heat. Is this normal for the evo as my other cars do allow the ac to be on to dry out while the heater is on.

 

My friend sent me what I was asking about. Temp knob on heat and ac button lights up. For some reason mine doesn’t. Where should I start? Ac works when temp is on max cold only.

 

i'd check the refrigerant first, see if pressures are enough to turn the AC on

 

good call, I’m just basing it off of Max AC blows ice cold.

 

Your friend's AC light is on because he has mode dial on defrost. Running the AC compressor helps dry out the air, which helps defrost the windows better.

 

I understand that, I’m wondering why mine doesn’t turn on with defrost.

 

Bump for an update. It seems even though the ac light does not turn on when in defrost setting, the compressor does kick on. Ac light will not turn on in any setting / temp or position unless on max ac.

 

Did a bit more digging today, knob turned to any defrost setting, ac compressor does engage, ac light is still not on. Ac light in any position is on only when in max ac. Ac light will not turn on for any temp, or position if not in max ac setting. I also found my passenger vent does NOT get as cold as the driver side. I’m unsure if this is a related issue.

 

if that bothered me I'd check out the bulb or the connector. maybe your headunit knocking something off. if that not it I'd probably buy a used unit from ebay. that button looks generic

 

the one pictured is my buddies, not mine. He sent me that to show me that his light turns on. I will recheck my connectors but I’m curious as to why mine doesn’t turn on in the same position his is set at. Do you have a picture of what yours looks like?

 

yeah i know. i mean that button/panel can be replaced with controls from other mitsu cars, if you really want/need to replace it

 

this hvac control unit came out of a 05 lancer but I’m unsure if it’s correct as the part number said certain year Evo’s and some lancers.