The invention relates to an automobile combined meter having an automobile
electric control diagnosis function and a diagnosis method thereof. The automobile combined meter comprises a central controller, a meter interface, a plurality of multifunctional indication step motors electrically connected with the central controller respectively, a meter illumination indicator lamp, a
safety status indicator lamp, multifunctional indicator lamps, multi-
fault indicator lamps, a display screen, a
clock chip, a storage, a voice prompt module, a key
processing circuit, a
power module electrically connected with the meter interface, a plurality of input
signal processing circuits electrically connected with the central
control unit and the meter interface respectively and an automobile
electric control diagnosis interface circuit, wherein a controller
area network (CAN)
bus interface and a universal asynchronous
receiver /
transmitter (UART) interface are arranged on the central
control unit. When the automobile combined meter used, the meter interface is electrically connected with the
electric control unit of the automobile to be diagnosed, and the central controller is connected with the automobile electric control diagnosis interface circuit through the
CAN bus interface or the UART interface and then communicates with the the electric
control unit of the automobile to be diagnosed through the meter interface. Having the automobile electric control diagnosis function, the automobile combined meter can prompt the fault of the automobile and make the fault point clear so as to prompt drivers to maintain the automobile better.