When does AC turn on?
 

In my 2005 Shinka I have an interesting issue. When starting the car the AC is sometimes on, and sometimes not. I have tried without success to find any reasoning behind what causes it to come on. It seems to be completely independent of outside temp and/or HVAC control settings. Up here in oregon I rarely ever need the AC, so its easy to notice when it decides to turn itself on that I did not leave it on by accident.

I did have the issue with the HVAC control knob sending erroneous temp values, but that was fixed by the dealership(warranty) and I haven't had any issues with that knob since.

Has anyone else had this problem?

????

Do you have automatic climate controls or something?

Pardon me asking, but if the manual fan speed knob is set to 0, the A/C never blows. Plain and simple.

Ha ha! This is interesting. The op might have a automatic climate control device and don't even know how to operate it, lol

When it's 40 degrees outside and the AC turns on..something is a bit wrong.

AC f(x) is active when fan knob is above '0' and:

- AC button 'on' (light)
or even wo/that
- air flow direction is to floor (AC indicator does not light)

Please don't tell me you have the non-recirculate button (vent) button on...

Also, a small amount of air still flows through without the A/C being on and in recirc. The temp dial even works on this tiny amount of air. But we're talking a very small amount. Like 1/8th the amount of air that the A/C pushes with the fan on 1. Maybe this is what you're talking about? Every car does this...

But the A/C just doesn't turn itself on. It's not a house.

*sigh* ...the problem is this...

I turn on the car and one of two things happens:

( fan setting of '1', temp on fully cold, intake on vent..this does not change)

A) the AC light stays off and I go on my merry way.

B) the AC light comes on and the air is noticeably colder...I wonder for a second if anyone else has this happen....I turn the AC off...and go on my merry way.

Sounds like your temp control assembly. When you have the blower on anything other than off, and you turn your temp knob all the way to max cold, the a/c button comes on automatically. I think your "detent" is worn, so sometimes it thinks you moved it to that position? Either that on your a/c button is sticking.

In any of those problems, a new control assembly sounds like your fix. Thought they sold reman ones but I guess not.

http://www.finishlineperformance.com...cat=298&page=1


*edit* some have found ways to fix it:
https://www.rx8club.com/series-i-do-yourself-forum-73/diy-no-heat-repair-heater-control-158200/