I have solved this problem, but thought the electrical experts might try their hand at diagnosing this problem.
My father in law made a homemade extension cord. He took a 12/2 wG cable and put a plug on one end. He wired a box with a SPST ON/OFF switch to the hot wire. He then wired the other end with a duplex 15 amp outlet.
When he plugged ANYTHING into the outlet, it would not work. It was like it had no power, so he called me. (I have a reputation of being able to fix anything.)
I plugged in one of the 3 light testers.
With the power switch turned ON, all 3 lights were lit.
With the power switch turned OFF, the red and middle lights were lit up which normally indicates a hot/neutral reversal, but the right light was not on. Note that this is with the power switch turned OFF.
Anyone care to guess?
Bobbo and Lin
2017 F-150 XLT 4x4 SuperCab w/Max Tow Package 3.5l EcoBoost V6
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