This reminds me of an old television (CRT) I once "repaired". It already was over 10 years old, and would not turn on anymore. After some poking around and reading datasheets, I discovered it did a "beam current measurement" during the boot process, and would not show a picture if that measurement was off. When fooling that measurement by momentarily adding a resistor, the CRT worked normally until powered down. My final repair was a resistor, a micro switch and a piece of string. So after turning the TV on, you had to pull the string to turn the TV on. It was good enough to get several extra years of use out of the thing.