A/C woes

[ignite]

Anyone know much about air conditioning?

'04 SE-R Spec-V

My A/C is stuck "on". Whenever the fan is turned on, the A/C kicks in regardless of whether I have the A/C button depressed or not.

For the past couple of days, the problem came and went (ie turn on the A/C, and then it wouldn't disengage), but now, its all the time...

Anywhere I should start looking?

[AzNKiD]

May sound like a stupid question, but are you on 'defog'?

[ignite]

I thought of that too, but no, I tried it on other settings too.

[civicgsr93]

HONDA FTW :P

Sorry Ben, I can't help you! Don't use your fan, use your pw for air

[CRXZC]

Not under warrenty anymore Ben? Maybe there is a recall or something, just call the Service Manager at the dealer, he might have some quick and common insight..

I really know nothing about A/C, I was thinking maybe it was the defrost thing...

-Mark

[ignite]

Lol, thx Jonathan :D

Yeah, good idea Mark, I'll give that a shot tomorrow!

[ignite]

Wow, Anzkid, you were close..

So, when I was trying to figure out my problem, I was putting the selector on the fan to defrost last (before shutting off the car) to see if the compressor would turn off at that point... When I restarted the car, the fan would be on defrost.

Apparently I stumbled upon a goodie not very well thought out by the enigneers over at Nissan:




Personally I'm rather annoyed by the A/C coming on automatically when you set your environment controls on defrost. That in itself isn't so bad, but the fact that you can then no longer turn off the compressor without restarting the car just drives me nuts.

glenstiles started a post http://forums.thevboard.com/viewtopic.php?t=13609 about this issue, and then DBAJonR posted a solution.

I ripped apart my dash today to fix it in my car, and found a solution that doesn't involve cutting any wires, allowing complete reversability later. Want to control your A/C with the button and only the button? Read on.

First, take apart your center console around the radio. The upper compartment and lower trim plate pop off with no tools. Then unscrew the radio and remove it. You will be left with a hole that looks like the picture below. The wires causing the problem are highlighted.



The wires travel around the control box to the underside, where a microswitch is hidden. Remove the 4 screws holding the controls in place, and then rotate the controls as shown below to slide them out to where you can work on them. You have to push against the control cables a little to do this, don't be afraid.



Now you can see the microswitch and the mechanism that activates it underneath the controls.



The switch is a generic spring loaded 2 way switch. It is wired to be NC (Normally Closed) which is why DBAJonR's snip-and-solder mod works. You're keeping the curcuit closed, preventing the auto-engage.



Take a small Zip Tie, and insert it under the metal tab, next to the switch's button. This will prevent it from being triggered. You could also break off the end of a toothpick under it and then electrical tape it, but that's messy. In reality, this step is not absolutely required if you're not worried about something hitting the switch, but I'm paranoid and I don't like ripping things apart twice Very Happy



The hole in the control panel that mounts the switch to the underside is drilled all the way through. This allows you to screw the switch down to the top of the housing, securing it to prevent vibration and keeping it from touching anything. It even clears the radio in this position.



And there you go. The A/C now will only run when you push the button, and will shut back off when you push it again, regardless of the vent control position. And the best part is, it's completely reversible. Should you ever decide you want this "feature" back, just cut the zip tie and move the switch.

Hope this helps everyone who hates this bit of engineering genius as much as I do! Mr. Green



I'll go out and check at lunch just to make sure..

[AzNKiD]

Yay, me.