# No AC Compressor Power



## Dmillzz32 (Feb 28, 2017)

I am the owner of a 2006 Nissan Altima and I recently purchased this vehicle with it being known that it had AC issues. The dealer I bought it from had the compressor replaced but still the ac was not blowing cold. The mechanic from the dealer said no power was being supplied to the compressor so it was still blowing hot air. It was suggested that the IDPM might be the source of the issues so I had that replaced. Still no cold air is being blown. The freon levels are good and idk where to turn next. The mechanic I have is also confused too so I haven't been charged any. I just wanted to see if there was anything I could do before I give in and pay big bucks at the dealership


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## quadraria10 (Jul 6, 2010)

Why don't you have a look at the service manual for your model and read the ac section. 

https://ownersmanuals2.com/make/nissan/altima-2006-4261

Its either the mtc or atc section depending upon whether you have climate control or manual settings.


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## rogoman (Dec 16, 2004)

With the A/C on, it’s normal for the compressor clutch to regularly turn itself off and on. If the compressor doesn’t turn on at all with the A/C set on max, there could be something wrong with the compressor. But you won’t know for certain until you check the pressure with a manifold gauge set. For this test, use only the low side gauge. When the compressor is not running, the pressure will be higher than if the compressor were on. In other words, if the gauge reads in the “normal” range with the compressor off, then it’s actually low on refrigerant. Low side normal gauge readings, when the system is running, are generally in the range of 30 - 50 psi depending on outside temperature.

Compressors are designed to shut themselves off if the refrigerant level gets too low. So, if the gauge reads in the “low” or even the “regular” range, the compressor might be working as designed and simply need more refrigerant before it will turn on. You can test this by adding a few ounces of refrigerant. If the compressor then starts running, you know that the problem was low refrigerant.

If the compressor does not turn on after adding some refrigerant, or if the gauge reads in the “high” range, then there may actually be something wrong with the compressor itself.


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