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AC clicking, not cooling, (started to grind under hood)

We have a 2003 Nissan frontier pickup (automatic).
The AC recently stopped cooling, but the fan works. It was cooling perfectly great when all of a sudden, it stopped.
If we turn the AC on, the compressor (I’m guessing) starts to click and continues to click until turned off. It’s not a rattle, definitely a click as if it wants to turn on but can’t make the electrical connection. It kind of sounds like when a starter has gone bad and it clicks. Except, it does it repetitively until turned off.
This doesn’t happen if we turn on the fan but leave the AC off.
Does it sound like the compressor went out? How can we troubleshoot it?
Thank you!!

Sounds like the compressor is bad, but could be low refrigerant. The only way to find out is hook up gages.


and if we just put a whole can and the gauges said it was at max…

It may be over-filled.

The problem existed prior to putting in Freon. Husband put it in thinking it would fix it, but it didn’t.

Maybe the compressor clutch ?


we will check into compressor and related mechanics. Thank you. Is there a way to test it out ourselves to know for sure before taking it to someone?

I believe there has been some compressor module problems on the Frontiers. It could be the module is kicking the compressor clutch on and off.

Of course, I have no idea what the system pressures are and if something is not right there the compressor clutch can also kick on and off.

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so, ur $20 freon can with high tech gauge says system pressure is fine? The fact u were 1 can low on freon makes me believe ur system is not fine.

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You can look at the compressor and see what it is doing. If you open the hood and look at the engine, the compressor is a thing that is driven by a belt, and looks like it turns all the time when the engine is running. There is a clutch in the pulley that clicks when it engages. The pulley turns when the engine is running, and the clutch engages when you turn on the AC. If you watch the engine start (hands in your pockets) and then watch and listen as someone turns on the AC, you should be able to locate the compressor by the loud click, and you might even be able to see the center part of the pulley begin to turn.
If it keeps clicking on and off, something is wrong with it. For most people the solution is an auto air conditioning specialty shop.

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your a/c compressor clutch is controlled by sensors that read pressure- both high and low. You could have too much ‘Freon’ in it now, or not enough. or one of these sensors could be going bad.
Even though auto stores sell cans of r-134a doesn’t mean that these systems are easily serviceable by untrained ‘professionals.’ Without hooking a good set of gauges up to this system, you are really just guessing at what the issue could be. Your best bet is to find someone who actually knows what they are doing and has the proper tools to check and troubleshoot this system.

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thank you. i’m just relaying info that my husband is giving me in pieces
and chunks. He doesn’t explain himself well enough for me to get the whole
picture. He always puts Freon in our cars and never has issues, but who
knows. He’s not trained. He might not have put a whole can, but the prob
def existed prior to Freon being added.

Your freon charge is within acceptable range (although it might not cool as much as you want). Pressure sensors attached to the “high” and “low” a/c lines monitor the pressure inside the lines. The compressor would not engage unless the pressure is within a specific range.

When you said the fan is working, I assume you mean the cabin fan inside the car. If so, you need to check the condenser fan as well. It should always run when the a/c is turned on.

If you hear a click when the a/c is turned on, you hear the click of the coil attempting to engage the compressor clutch. Therefore, freon must be within acceptable ranges.

Correctly, another poster here said to observe whether or not the clutch engages and turns when you turn on the a/c. If the clutch does not engage you may have a bad coil or worn clutch. An experienced mechanic should be able to diagnose this easily.

Fixing it depends on the location of the compressor and how difficult it is to get to the front of it, but would say not more than 3 hours. Parts should be relatively inexpensive as well. I recently purchased a new coil for $65 and that was expensive.

Forgot to mention…yes, you might be able to test this yourself. It depends on how easy it is to access the compressor. The clutch is located in front of the pulley that turn the compressor. When the clutch is NOT engaged it just sits there and does not spin together with the pull. When engaged it spins in tandem with the pulley. If you have easy access to the front of the compressor have one person turn on the a/c inside the car while you observe the clutch. You should see it engage as soon as the a/c is turned on. If the clutch does NOT engage give it a quick tap with a hammer or some other object. Many times this will engage the clutch and keep running as long as the a/c is on, but will NOT fix the problem because the next time you turn on the a/c you will have the same problem again. It only demonstrates that you have a clutch assembly problem. WARNING: do not do this if you don’t feel comfortable working around a running engine with belts turning.

Sounds like it’s time to take it to an a/c shop.

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I agree with texases.

For even a hazy guess to be made here the system low and high pressures need to be known. I’m not a fan of those charging cans or those TV commercials which make it appear that anyone can be an A/C pro.

Such negative vibes @ok4450!!! Miracle in a can.

I dun took da Evalin woodhead sped reddin and ritin corse and look at me!!!

They will make any claim they can to sell their product.


When my brother’s Nissan pickup did this, it was a plugged AC receiver/dryer. He replaced that and all OK.

We had a Nissan guy look at it. Clutch. It was starting to grind, so we will be replacing the whole compressor.

You nailed it. Thank you.

You’re welcome , it would probably be less expensive to just replace the clutch .