Automatic climate control, A/C

PHW

MEMBER
2005 HYUNDAI XG350
3.5L
V6
2WD
75,400 MILES

When I start the car for the first time after sitting overnight, the A/C system blows nice and cold for about 3-4 minutes; then the compressor shuts off and the air slowly gets warmer. When the car is warmed up, I can't get the compressor to come on at all. The system is fully charged with refrigerant. The compressor and associated components were replaced about 6-7 months ago. The automatic climate control module was replaced 3 weeks ago. What could be the problem? Help!

1 Reply

KASEKENNY

MECHANIC
18,907 POSTS

There are a number of things that could cause this, but we need to start with checking the Freon level.

I understand that it may be full, but you have pressure sensors that will cut the compressor off if it is too low or too high.

So, your issue could be that the compressor runs, and the pressure rises, and it gets too high and cuts the compressor off. Normally it will turn back on when the pressure comes down but if you have a restriction in the system then that may hold the pressure high.

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

So, running the engine with a pressure gauge on the high and low side will tell us what is happening when the compressor is cut off.

Even if this tells us that the pressures are normal and that there is no issue then that will tell us that the control side is the issue. However, we must start with this and go from there.

I attached a chart below that will help with proper pressures.

Thanks

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