my ac turns off when set to full blast???

[xkrisx]

I have a 1991 240sx hb.ka24de

My air conditioning will turn off when I turn it to full blast on setting 4. Settings 1 through 3 work perfectly fine but only when I turn it to the 4th setting the ac compressor clicks off and the light on the ac button goes off and it starts blowing normal warm air.

I already replaced all my relays/fuses/and blower motor resistor, with no luck. I'm starting to think I might have to replace the heater control unit?

Have any of you heard of this or experienced this?

Any help will be greatly appreciated.

Thanks,-Kris"

[gripstr]

You wont happen to have a digital climate control would you?

Try replacing the whole control unit or borrow it from a friend or fellow s13 owner and see if that fixes it.

[xkrisx]

You wont happen to have a digital climate control would you?

Try replacing the whole control unit or borrow it from a friend or fellow s13 owner and see if that fixes it.

Thanks I'm gonna try replacing it.

Buying one off eBay, i'll let you guys know if that was my problem when I get it.

[lrb_2000]

Mine does the same on my 95. Except it's the number 3 setting. It's probably just the unit itself. The lights inside randomly come on and off.

[youngun21a]

same thing it turns off on 4

[dkdeleon68]

Take the control unit out and clean all the contact points. a very simple fix.

[cody180sx]

mine does the same i think the copper contact is bad ar it comes off the track or something just set it to 3 and a half