Automotive Air Conditioning Information Forum

I have a 2015 Lexus NX.

The issue is that the AC is not as cold as it should be. When it’s set to full cold, the pass side feels a little cooler than the drivers side, but still not “AC cold”. I understand this usually means a low refrigerant charge. Otherwise, the HVAC operates as it should.

I have confirmed that the vehicle has the correct amount of refrigerant and has no leaks (took it to a shop).

I have Techstream, and did have code B1441 (Air Mix Damper Control Servo Motor Circuit (Passenger Side). I cleared the code and it has not returned. I have also used the test functions to test all of the servos, and they appear to all be working. I also initialized the servos.

The compressor is a variable one (not the older magnetic on/off style).

I also have a set of AC gages. When cooling, the low pressure side is 30-40, high pressure is 90. Outside temp was about 8-10c.

Thermal expansion valve?

Cabin air filter is good.

Before I drop it off at a shop, what else can I check??

At a maximum ambient of only 10°C (50°F), it's just too cool yet to test A/C performance. At that temperature, the compressor is probably running at minimum displacement. Suggest waiting for warmer ambients--at least 27°C (80°F)--for meaningful system testing.

Appreciate the reply. I’ll wait and retest.

Just curious...is your 2015 Lexus NX a hybrid?

Not a hybrid.

It was warmer today:

Outside temp it 18c/65f

Low pressure is 21-26
Hi pressure is 125-140

Output temp is 11-12c, 52-55f.
Does have dual zone, pass side is cooler than the drivers side.

Lexus NX 2015, the compressor is a variable type (no clutch).

Compressor issue? Expansion valve problem? The solenoids under the dash have been confirmed to work.

I have Techstream, and it passes all the tests.

When I turned the car off, low went up to 45, hi stayed about the same at 140