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Discussion Starter #1 (Edited)
Okay, I have a 2012 Focus SEL with Electronic Climate Control. Suddenly, the A/C Compressor does not engage. Blower motor and all associated HVAC controls work.

1. Confirmed there is the proper amount of 134a Static is 70 PSIG both High and Low Side.
2. Confirmed Fuses #23 / #27 are good.
3. Confirmed Relay Operation
4. Confirmed Wiring and Connections
5. Confirmed PCM Command to Circuit
6. There are no codes for HVAC CAN indicated.
7. Transducer has 5VDC Ref Voltage, Signal, and Ground (Pin#1 4.8 VDC Pin#2 5.7 VDC Pin#3 4.8 VDC)
8. KOEO HVAC CAN Test shows no problems

I can power the clutch manually (-) Side with 12VDC. The system works well. So, the compressor works as it should. If I cycle at about 28 PSIG it makes ice cubes.
You can review the scan data here. Maybe it will help: https://www.dropbox.com/s/bn3c5wwhrav8fz4/Scandata.jpg?dl=0

Anyone seen this prior?

Thanks, Tom
 

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WOW! Never heard of this happening on a car so new... But you pretty much did it all and all seems to be fine and it obviously is if you can jump the compressor and get cold air... sooo check low and high side sensors?

I'd imagine it's still under warranty right? I'd have them check it if so and get some free parts out of it...
 

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Discussion Starter #3
WOW! Never heard of this happening on a car so new... But you pretty much did it all and all seems to be fine and it obviously is if you can jump the compressor and get cold air... sooo check low and high side sensors?

I'd imagine it's still under warranty right? I'd have them check it if so and get some free parts out of it...
This was actually a Salvage Vehicle with just enough damage to total it. There is no "low and High" Sensors.

The "newer" Fords use a Transducer and vent temperature to command the PCM to switch ground and cycle the compressor via the Transducer. First came along with the Lincoln Continentals a few years back. Then they introduced to the Fusion. What a nightmare! You had to remove the entire dash to change what turned out to be defective sensor EVTS (EVAP Temp Sensor).

Hopefully someone will chime in. Usually if the sensor is defective it logs a code to the history.
 

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'Usually if the sensor is defective it logs a code to the history.'

Famous last words and I note your use of the word 'usually'............

I know nothing of that late model stuff..........as in.........what does 'refrigerant pressure middle pressure' mean? I note it says off. Detail that if you will.

If you have done all testing and the results say good then somewhere a sensor is not sending back (on its' own) what the PCM wants to see. Or possible PCM issue though rare. You don't reckon accident could have..........?
 
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