2012 Fiesta DTC U0401 error, any help?

Maintenance/Repairs
1

Hello, I want to ask about my complicated error on my car.
My car run smoothly and sometimes the traction control and hill start assist lamps went on with a chime sound. The lamps went off when I restarted my car, and it went on again randomly.
I checked with my OBD tool and it seems i got a U0401 error code in 2 modules: TCM and ABS (screenshot https://imgur.com/a/bZHeZeO). I aware of the B1193 code (my airbag went blew, it was few years ago). My 4 speed sensors is good and read well.

I already checked in the internet and it seems there is some causes: wiring, faulty sensors, or bad voltage. And I read that maybe the camshaft position sensor is faulty (I suspect this too, but it will be waste if I replace the sensor and the error still occurs).
I get ~13V ECU volt when my car stands by with engine on, is it normal or not?

Then, I tried to test my PCM and it shows P1464 error (A/C Demand Out Of Self Test Range). there is no errors if I tested it without A/C. Is there any connection between this AC sensors with the network error?

It seems that the 2 lights went on randomly, I don’t know where to check first, the wiring or sensors. Any help would be appreciated. thank you.

2

The communication to the ABS/Traction control computer (it is the same one) is not working. This ECU needs to be able to receive data from the engine and send it back to make the traction control work.

Why is the communication missing? Bad ABS/TCS ECU or damaged communication wires. Given that this car has been in a wreck - why else would the airbags go off - I’d start looking for damaged wires going to the ABS unit mounted under the hood. Check the connector carefully WITH a wiring diagram showing the color of the comm wires. Given the accident, I’d guess the ABS/TCS is damaged and will need to be replaced.

The camshaft sensor is not the issue nor does the AC affect it. 13 volts while running at the ECU is fine so that is not your problem.

The P1464 is an AC problem separate from the U0401

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