im new to this forum i have an issue the previous owners of my sc300 wired a switch into the dash next to my steering wheel. i guess the fuel pump or fuel cell has a seperate pwr wire from the harness or something. and the only way i could start the car is if i turn the switch on. so one night i left the switch and turned the car off for the nite woke up the next morning tried to start car no dash light no crank nothing so i thought ok battery died took it to get it charged and put back into my car had dash lights but no crank no start dont know wats going on help please

 

Check if the fuel pump is primming or Working. If it is u should hear a buzzing sound. So then I would check the starter.

 

Check that switch if there is any loose or disconnected wires. Follow those wire to see where it leads(starter, fuel pump, etc) and check if those wires are connected. If all checks out good, I would try replacing that switch with a new one.