Ford Focus Mk3 EU - PCM.INCARTMP has 215° C and AC not working

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Posts: 16
Joined: Sat Nov 21, 2020 12:30 pm
Vehicle: Ford Focus EU Mk3, 2015, 88KW/120PS, 1.5 TDCI, XWDB

Ford Focus Mk3 EU - PCM.INCARTMP has 215° C and AC not working

Post by pfeilmayer »

Patient: Ford Focus Mk3, 2015, 88KW/120PS, 1.5 TDCI, XWDB
Symptoms: AC does not work (does blow cooled air), compressor (and fan) do NOT engage / turn on.

What I've done so far:

1. Diagnostics. I have NO DTCs on the car, none whatsoever.
1a. I also read the information in real-time, the video with the data will be posted in a link below.
2. I checked ALL the FUSES in the 3 fuse panels: under the hood, in the passenger compartment, in the trunk. I have NO faulty fuses!
2b. I checked ALL the RELAYS. I have NO faulty relays!
3. I checked the pressure in the installation, and the pressure seems correct, KOEO with AC off, the pressure is identical on the HI and LOW sides (18 deg. C, +-30 PSI). At least according to the Pressure & Temperature Chart for R134a refrigerant.
4. I replaced the pressure switch/sensor (Pressure switch, air conditioning, Article number: OEN Part 5471192/ MEAT & DORIA K52097, EAN number(s): 8033208222105 - the fastest part to change so I have no other doubts regarding the sensor). Conclusion: the old pressure sensor is either good or the new one is defective. Probably both are good. OEN Part 5471192/ MEAT & DORIA K52097
5. I optically checked the 2-pin plug that goes into the climate compressor and the harness and I did not find any broken cable, eaten, cut, etc., under the car!
6. I measured if the compressor receives voltage. Here I discovered the first bug: NO, the compressor, on that 2-pin plug, does NOT receive voltage, although according to the button pressed and confirmed by the diagnosis, the command to start the AC exists!
7. To rule out the compressor/electromagnet, I fed the compressor directly, with other wires, from the car battery, and immediately the electromagnet/clutch engaged and started spinning.
8. With Forscan and Launch, the reading at "x1000 CACRP" is 399.0, with slight oscillations up to 401.0 (expressed in kPa). Ist the same when I have the engine off (Key On Engine Off) or with the engine running and if I'm not mistaken even when the engine is on and the AC is "on". („on“means that it is set to a minimum temperature, on auto or manual with maximum speed and the AC button pressed ...
9. The Pressure Sensor voltage is about 0.82V - 0.88V as shown in Launch and Forscan

Videos related up to point 9:
Diag Data Stream
Diag Data Stream 2
Refrigerant Pressure (important to mention: here I was powering the compressor/clutch externally with 2 wires directly from the car battery)

10. While bypassing the relay with a jumper cable to power the compressor on, I topped up with refrigerant fearing that the pressure is too low
11. Replaced the In-Car Temperature sensor (BM5T-8B506-AB). Hopefully, the right one though I tend to think this is IAMT and has nothing to do with PCM.INCARTMP, after someone pointed that out, unfortunately too late.

The latest things I've done (Points 10 and 11) :

Please tell me what/where this PCM.INCARTMP sensor is and why does it show 215° C on 3 different diagnostic tools (Vlinker MC+ - ForScan, Launch X431, AutoC/Deplh Clone) including ForScan.

Is it possible that this 215° C temperature is an error in the PCM?
Do you think I should reflash the PCM through ForScan?
If yes, is there anything I should pay attention to?

Thank you
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Re: Ford Focus Mk3 EU - PCM.INCARTMP has 215° C and AC not working

Post by FORScan »

215°C means that PCM returns 0xFF value . The formula is Y = X-40 where Y is value in °C and X is raw data read from PCM. 0xFF = 255 decimal, thus 255-40=215.

The 0xFF value usually means that the PID is either not supported by the PCM (so diagnostic interface of the PCM supports it for some reason, but the input is not connected to any sensor), or the sensor is malfunctioning. In your case, considering there is no any DTC about the sensor, we would assume the PID is not really supported.
Don Ridley
Posts: 716
Joined: Sun Apr 01, 2018 2:31 am
Vehicle: 2016 Transit Connect

Re: Ford Focus Mk3 EU - PCM.INCARTMP has 215° C and AC not working

Post by Don Ridley »

Try monitoring all PIDs related to the air conditioner in the PCM and BCM. Look for a failure like the "AC on" switch does not change states when pressed. Also look for states that turn on then off quickly or are very noisy.
Posts: 731
Joined: Sun Sep 16, 2018 1:35 pm
Vehicle: ford focus 1.0 ecoboost (100ps) 2017

Re: Ford Focus Mk3 EU - PCM.INCARTMP has 215° C and AC not working

Post by Andyfocus »

i would start by again removing all refrigarant from the system and refilling , as over filling the system will have the same effect as underfilling it and it will NOT work , as you have said you have filled it then filled it again because unknown reason just says u started car and refilled again after filling it ?.
i am the same as you just a forscan user still learning .
The search function is there for a reason use it.
no you can no longer pm me with your 1 or 0 posts so dont try.
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