Woody Prusa 3d Printer Repair Time

I've got some sort of problem in my 3d printer with the bed leveling probe, which is a proximity probe the printer uses to figure out how hight the print head is from the print bed.

It is probably a wiring problem; wiring is by far my weakest skill in playing with 3d printers. I probably have some dodgy tiny wiring problem in a solder joint or a splitter cable. I figure after 2 years by

When I first built the printer I had some trouble with probing. I thought it was a problem with the probe or my setup but it was the particular bed surface.

Anyway I have a spare probe and also found a supplier of a splitter cable I need, so one of those things is likely to fix my problem. I'll start with the splitter cable change, from my dodgy part which is a three way solder of three cables to a professionally assembled one without any soldered wires.

A guide about the splitting and which wire goes which way is here, along with some Marlin config things.

https://www.youtube.com/watch?v=AjB0ZucPf9s&t=177s

Cloned Prusa PINDA 2 probe.