Electronic control device for engineering machinery and working method

The invention discloses an electronic control device for engineering machinery and a working method. A controller is connected with a parking brake switch, a handle meso-position switch, an accelerator idle switch, a starting switch, a starting relay contact, an engine ECU (electronic control unit) and a flameout switch. The engine ECU is connected with an engine and a starting relay coil, one endof the starting relay contact is connected with the controller, the other end of the starting relay contact is connected with a starter, and the controller is further connected with a brake valve. The emergency flameout switch and a power forced recovery switch are further connected between the controller and the engine ECU, and an emergency brake switch is further arranged to control a power supply of the whole electronic control device. Damage to the engine and a pressurizer caused by improper operation in the starting and flameout process of the engine can be avoided, damage to the starterand a storage battery cau