A/C compressor not cycling on or off

NISSANGUY04

MEMBER
2004 NISSAN FRONTIER
2.4L
4 CYL
2WD
MANUAL
179,000 MILES

My A/C started blowing hot air recently. After a brief check I found a leak on the high pressure hose which was replaced. A/C now blows okay, but lately I noticed that the compressor is not cycling on and off. The compressor was cycling on and off when my mechanic friend vacuum and recharged the system. Now it runs constantly without clutch disengaging. Just to add the fan and A/C on/off switch works okay. Both switches disengage clutch when set to off. Is this something I need to worry about? I live in Florida. Also, if I need to change the pressure switch can I do so without recharging the system again? Thanks for your help.

3 Replies

JACOBANDNICKOLAS

MECHANIC
109,885 POSTS

Welcome to 2CarPros.

Based on your description, I have a feeling the system is low on Creon. Is it possible to have your friend check both the high and low side pressures and let me know the results?

As far as concerns, based on demand, the compressor may stay engaged. It has a high pressure switch which will turn it off if there is too much pressure. That is why I am thinking it could be low on Freon.

To answer your question, if you remove the pressure switch it will need recharged. See picture 1 for sensor location.

If you want to try to add Freon yourself, here are a couple links you may find helpful:

https://www.2carpros.com/articles/air-conditioner-how-to-add-freon

https://www.2carpros.com/articles/re-charge-an-air-conditioner-system

Let me know if I can help.

Take care,
Joe

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