My imaging unit did not have a resistor either so I twisted the resistor onto the two lowest contacts on the door (where the resister unit should touch if there) and powered the unit for a few minutes and the light went out. I then pulled off the restistor. I have the original imaging unit and mine is a C410W.
That worked for me.
PS. If at first it does not work then leave the resistor on and wait for all the printer to do its fits and stops and the light should go green. Then turn it off and pull off the resistor