If you do not know how the firmware and / or the temperature control works then you should not try to compensate you lack of understanding by completely ruining the system.
Let me guess, if you have a faulty light bulb in your home you first rip out the wiring from the walls to check if that runrs the light on?
Did you consider the most obvious reason for your problem?
Like: You bought a printer that is only rated by the manufacturer for PLA and nothing else?