Following possibilities could make Platform too hot error :
1.Platform's FFC cable not connect well- Re-insert it and give another try. If the issue still happen, then change to another new FFC cable.
2. Aluminium build plate broken-there may be any short circuit on it. Need to be changed into a new one.
3. There is a temperature controler in the mainboard, the wire connection is not solid, or etc., may cause the motherboard to be short-circuited and burn out the temperature-controlled switch. Need to change to a new mainboard.