VRef Voltage 'A' out of range

[Seishuku]

Today I went to drive my 2015 Mustang Ecoboost, no accelerator pedal and DTCs for pedal (D or E, I don't remember which) and vref 'A' range (P06A6).
I'm not entirely sure if the pedal itself is bad, I bench tested it and I get sweeping voltages on it on both circuits... But when checking vref voltages at the pedal connector I get +5v on circuit B, but +10v on circuit A.

Is there maybe another sensor on circuit A that could be shorting the vref to battery? I'm assuming both vref circuits should be +5v.

I haven't done anything to the car except for change the oil over a week ago and drive it, though it was raining pretty heavy yesterday when I was driving home from work, but it drove perfect. Just next day, suddenly these faults.

Anyone have any ideas?

I can still start the car and it idles perfect, I can even move it around under idle power with no issues.

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[Seishuku]

Alright, made some progress... Unplugged the ECU and the short went away, but there are 3 pins on the ECU that are vref 'A', 12 13 and 14. Only 12 and 13 are used, 12 is APP vref A, the harness side isn't shorted, but pin 13 is... Which according to the ECU pinout is for the fuel tank pressure sensor.
I think that's in the same box in the rear with the EVAP stuff, so that narrows things down.
But why that would be shorted to battery, I don't know yet... I don't think there's anything back there that's battery voltage other than the EVAP pump.

 

[Seishuku]

In the unlikely case that anyone has this same problem, check the connectors in the driver's side footwell, specifically the grey one.
Apparently that connector has the driver's seat +12V feed right next to the vref 'A' circuit, in my case the connector was soaking wet with condensation from shoes/carpet and it caused some corrosion to track between the two pins.
Blasted out all the connectors in that area with contact cleaner and gave them all a good blast with dielectric grease, it's all good now.

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