Back accelerator electric control method and system

The invention discloses a back accelerator electric control method. When component maloperation or line short or disconnection happens in a standard control unit, a first back accelerator, a comparing control unit and a second back accelerator, a standard control signal forwarded by the first back accelerator forwards and/or a comparing control signal forwarded by the second back accelerator will change so that the standard control signal and the comparing control signal cannot keep original proportional relation, at the time, a chassis ECU cannot convert the standard control signal to a control signal and carry out sending, and rotating speed of a chassis engine cannot be driven to be changed. The problem that in the prior art, when component maloperation or line short or disconnection happens in the control units and/or a back accelerator part, the rotating speed of the chassis engine fluctuates, and fuel is wasted is solved.