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So my wife's R33 A/C has been acting kinda funny lately. Even with the climate control turned completely off, the A/C still stays on. It blows very cold and all of the mode/blend doors are working properly, but it just won't stay off. Any ideas?

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Very good question! She says that she notices that the compressor cycles on and off even when the climate control is turned off completely. She does notice that when she has recirc on and the Climate control off she doesnt feel cold air blowing through the floor vents. But if she has everything off and its on fresh air even on a hot day she still feels cold air on her feet. I have rode with her and experienced this as well. I just cant figure out why the compressor is getting power with the climate control turned off completely. Possibly a stuck/shorted relay?

Edited by Gojira5767

Hi Gojira,The ac system has a self diagnose system,do a google search you might only find it for the R32,but it's similiar in function. hope this help's.Here u go found it for u http://www.gtr-owner...ic-ac-test.html.

Edited by I gotta R34gtr v-spec

Maybe you're hearing the AC fan kick in, not the compressor? the AC fan will kick in automatically when the coolant temp goes over 95C. Naturally you won't even realise coolant temp is 100C as the coolant temp gauge doesn't really go near the red till about 120C

Ok, so I ran the diagnostic and came back with code 25(Sunload sensor). Does this cause the A/C to come on automatically when its faulty even when HVAC is turned completely off? Mode doors are all operational, and Diag Mode 4 shows "41"? Im assuming thats a blower motor check, as it turns it on during this mode. And on mode 5, the temp sensors are reading 31 & 32. Which I calibrated both to 31 degrees. I guess I need to replace the sunload sensor regardless huh?

Also, I haven't noticed the A/C fan kicking on, but then again the temp hasn't gotten that high. I have Power FC's on both cars, so I am constantly monitoring it. But your right, the gauge doesn't accurately reflect how hot its actually getting.

Edited by Gojira5767

If u did the test in the garage or at night u will get that result,u need to do it in the sun light.If u want to try the r34 service manual,here's the link http://www.importworkshop.com/files/manuals/nissan/R34_service_man.pdf and go to the a/c section.

That makes sense. I will try it again tomorrow then. And I think I have the R34 FSM printed off somewhere. If I cant find it I will definitely use the link. Thanks! This is just such an odd problem, something has to be sending power to the compressor at all times. I may just replace the relay for kicks.

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