2019 Expedition AC not working - recharge or pressure sensor?

[19ExpMaxPlatYYC]

I have a 2019 Expedition, it was intermittently failing, took it to the shop and they replaced the cabin air filter and it ran fine. Now its been sitting and the AC won't kick on. As far as I can tell the clutch never engages.

Forscan tells me the pressure is about 32 psi and barely changes at all 224 to 228 kpa, which just looks like a minute voltage change. There's a bunch of logic options to read in forscan on what is causing it not to call for ac - it never does. The one that is saying this is item 10 that says that a recharge is required. The obvious thing is to buy a can and try that, but there's also the distinct likelihood its the pressure sensor because it doesn't change at all when running or not. Of course, if the call for AC doesn't happen, there's really nothing going on in the AC system to change the pressure.

Thoughts? Is this a recharge situation or a sensor problem? I could test the sensor, but if I can't kick the compressor in to see if the voltage changes I'm not going to learn much.

In reading on this, I think a lot of people get screwed on a simple pressure sensor failure vs the repairs they get charged for.

Also, Ford lists HG1Z19D594A as the part but is 'unavailable', finding an aftermarket sensor is harder than I'd expect!

HG1Z19D594A

HG1Z19D594A

 

[AWAR]

We stocked the pressure sensor for the 17-22 Superduty trucks at the Utility I retired from. Common failure part. The part number may have been superseded. Did you contact Ford?

 

[AWAR]

 

[19ExpMaxPlatYYC]

Awar, any thoughts on DIY testing if its a leak or pressure sensor? Haven't talked with dealer, isn't available on their page...like you said, probably something superseded.

 

[19ExpMaxPlatYYC]

This is what they reference as a part number on their diagrams. Most of the part number is matching...

 

[AWAR]

We found the failure of the switch was that the system works and cools fine, then it cycles and does not come back on. We would evacuate and verify that the system was full and not leaking. We would recharge the system and replace the switch and the system would work as designed again. We have 16 trucks with this switch. I would keep 5 switches in stock at all times. I retired last year. These are R134 trucks not R1234. Check and see which system you are dealing with, we had compressor failures with the first R1234 trucks.

 

[19ExpMaxPlatYYC]

I used forscan to monitor the pressure, it was evident that sensor was working. Took it to the dealer for a diagnosis with the evidence from forscan that the AC interrupt 10 was saying I needed a recharge. That saved me half an hour of diag.

Ended up paying half an hour of diagnosis and $450 CAD for a recharge with due. They advised to drive for 800 km and if it didn't hold come back for a tracking of the leak via the dye.

A few things learned:

1. The condensers are $100 CAD from rockauto vs $600 from Ford.
2. One option to diagnose after recharge is to shut off the rear a/c, my assumption is that the condenser can be the more likely point of a leak. It didn't play out that way because the system leaked from 904 kpa to about 680 kpa in two days. I don't know if the shutoff of the rear worked or not.

I ended up with someone who wanted to buy the vehicle so that's the end of the story.

 

[AWAR]

Thank you for coming back with diagnosis and the ability to close this thread.