Hello, I have a problem with a cat ep20kc serial number ETB7A-005XX, it shows error code 30 when it is running for around 1 hour (when it goes hot), anybody knows what this code means? I tried with the little logic card in the right side (the one with a conector in the left side and other connector in the down side), tried also the traction transistors, and the pump transistor with no good results... Any help will be so much appreciatted.