i guys

i have a 2016 focus 1.5 diesel now the last few months i have noticed the car started to run on after shutdown with no dash lights saying anything was wrong. i thought nothing really of it but it started to sit in the back of my mind then i lately i got a engine service now on the dash so i plugged in forscan and got codes that that where out for the fault throttle body stuck open. i changed that and not the result i was looking for. so i tested all wires going to the motor and sensor and the seemed fine all giving proper readings so i though did a relearn of the throttle body still the same so i went back over the wires and found that when the ignition is on the earth to the throttle body has high resistance but when i turn the ignition off and the car goes into sleep mode the earth is perfect turn it on and high resistance again is this normal ?? it goes against my brains thinking. if im right is the PCM going bad it dose the same to the MAP sensor earth as well

thanks for taking the time to read

Phantom