A/C will not get cold until engine is at full operating temperature

[John's Island]

Hi, 

 

I have 2 dodge journey's with the same A/C issue that I can't seem to figure out. 

2014 Dodge Journey 2.4L

2015 Dodge Journey 2.4L

 

The issue is that the A/C will not get cold until the engine is warm. I know it's an issue with the fan control circuit. Can't seem to peg down what is causing the problem. The fan does not turn on when the a/c is on and the engine is cold. After the first 5-7 minutes it takes for the engine to reach full operating temperature, and kick on the cooling fan to bring the motor temperature back down, the a/c will work. It also intermittently stops working when sitting still at an idle (which seems to me that the cooling fan is just not being commanded on at those intermittent times because the engine isn't hot enough yet.) 

 

The following is things I have tested and/or replaced. 

 

It did have a leak in the high and low side pressure lines. I replaced both (they are a one piece unit) and also the expansion valve. 

I used a scanner to check the a/c line pressure sensor and it seemed to correlate with the gauges hooked to the service lines. Appears to be accurate and ok.

I used the scanner to check the control state of the fan. Both speeds work. Even so I manually tested each relay and they were ok. 

I used a scanner to see the evaperator temperature sensor and compared it to the temperature coming out of the vents when the a/c is working and it seems to be close enough to be accurate.

I replaced the low fan speed resistor with a new one I had lying around. Didn't help. 

I tested power and ground at the fan. Ground is good. Power is not commanded on until the engine is at full temperature. I can also provide power to fan to manually control it and feel the a/c temperature drop in the car. 

 

Basically the fuse, relays, resistor, and cooling fan all seem to be good. The system is fully charged and leaks were fixed and pressure is good and system blows cold when working. The wiring diagram I pulled from Mitchel says the pcm controls the ground for the fan relays. But I can't find anything that specifies what tells the pcm to do its job other than the coolant temp sensor (which seems to be working) and the a/c line pressure sensor (which seems to be accurate). Also the a/c button on the dash does light up. I assume that means the switch isn't open. And its a duty cycle a/c compressor that according to the scanner is being cycled on. This tells me that the a/c is being commanded on its just an issue with the fan control circuit. Does anyone have any suggestions or has anyone seen the issue before. 2 of the 5 Journeys we have are having this issue.  

 

Thanks.

Aaron