Was it DV or DK? DK is Drosselklappe - throttle plate.
When the throttle signal becomes unreliable it will cause the errors you see, and pass those on to traction control (which would do engine torque limitation by closing the throttle)
It all seems to tie in with the throttle signal though.
Yep, it's a built in part.
It'll work using about 5 different inputs, 2 potentiometers in the pedal, and both are checked against each other for plausibility, ie they both have to independently give a matching %, despite having different scales.
Once the ECU is sure, it'll then move the throttle plate, using 2 potentiometers again to check not only the position, but to check the other potentiometer too. Yet again, these signals both have to match, and they are on different scales, so shorting both the wires wouldn't make it look like Wide Open Throttle.
It also then has a third virtual potentiometer which is the air flow meter signal. It has to get an airflow signal that also matches what the ECU would expect at whatever RPM and throttle angle.
It's a very clever system used by most manufacturers which is why the jammed throttle stories on Toyotas have to be taken with a pinch of salt.
In a few of those cases, CCTV has spotted the car shooting off whilst the owner swears they are braking, with no brake lights on