Generic wire chasing:
1. Short to ground/signal out of range. = No
2. Connector not connected. = No
3. Wire out of connector. = Bingo!! (or the deeper troubleshoot is male/female pins not making contact is like saying the same thing.
Follow 3 fundamental variables with their own list of troubletree issues. Are there any other moves? No. There is fuel/spark/comp chasing a running engine. Are there any other moves than those 3? No. See the fun in the 6 fundamental moves?
I now start backwards.
1. Ohm is switched to 20 volts.
2. Key on, I prong to the headlight. Nothing
3. I remove the connector from the bulb. Do I have a good bulb? Yes.
4. I prong the wire out of the connector. Any power? No.
5 I find the next disconnect down the harness. I go back to the ohm's infinity scale. Are my wires broken from end to end? No.
6. I toggle back to 20v. I prong the next connector. Do I have current up to that connector? Yes.
7. I have good integrity from the sub-harness up to the bulb, but no joy at the sub-connector. #3 ~ Wire out of connector/no contact = Bingo!
a. My connector was connected = Not it.
b. No short to ground or open as if bulb was blown at the filament = Nope.
c. Male/female pin integrity = Bingo!
Work at the source on back, or start at the battery and work your way forward. Path is path and finding the break is all you are doing.