Hello to everyone and hope you're all doing well.
My kids just gave me a digital multimeter with duty cycle as a gift. When measuring the static reading with the red lead in pin #3 and the black in #2 of the X11 as per BOSCH KE3-JETRONIC MIXTURE ADJUSTMENT

The measurement with the key in the #2 position and the engine not running should be 70%. Mine, after numerous measurements, was 50%.
Anyone know why? Also, the reading with the engine running fluctuates so much, I'm not sure what my measurements are.
Anyone have a simplified explanation on how to read duty cycles on a 1991 300E? I've read every post in the search engine and on youtube.

Nick