A few week ago while driving at north on an unlit motorway I lost all instrument lights, indicators, side lights and cooling fan. Thankfully headlights and engine kept running until I got home. When I turned the engine off it would not then turn over. Further investigation found 3 blown 5 amp fuses the indicator flasher relay and the cooling fan relay. Never found out what caused the failures.
5 years ago with the ignition off and key not even in, if I turned the hazard warning lights on the fuel pump would energise and I could start the engine. This thankfully has sorted itself out.
I think you have multiple small faults which will be very hard to figure out, could even be as simple as corrossion in one or two multi plugs giving intermittent multiple faults.
