Vehicle display tool, comprising:a stepper motor (M), which includes a field winding (32, 33) and is rotated to the field winding when a control signal is applied (32, 33), the control signal being a alternating current which alternates according to a phase angle;a pointer (20) which points to a vehicle status value, which is shown with a zero value as a reference of the same, according to a rotating position of the pointer (20) and which is rotated in a zero setting direction (X) to return to a zero position indicating the zero value;a gear shift mechanism (G), which includes a majority of gears (34, 35, 36, 37) that are engaged with each other and which reduces a speed of rotation of the stepper engine (M) and transfers the speed of the stepper engine (M) to the pointer (20), thereby rotating the pointer (20),a stop device (S) for stopping the pointer (20) rotating in the zero setting direction (X) at a stop position within a predetermined range from zero in the zero setting direction (X);a recording device (50) to capture an induction voltage generated in field winding (32, 33) at one of a number of recording points (0d), which are electrical angles and contain a zero point (00) corresponding to the stopping position;a control device (50) to control the control signal related to field development (32, 33), where:an electric angle whose phase is moved to the zero point (tho0) is a waiting point (tho);an electric angle whose phase is shifted to the waiting point (0w) in a direction opposite the zero point (00) is a return point (thr);the control (50) performs a zero-reserve control, whereby the control (50) controls the control signal in such a way that the pointer (20) is turned from the standpoint (0w) to the zero-reserve direction (X),the control (50) performs a return control, with the control (50) controlling the control signal in such a way that the pointer (20) is rotated to the return point (THOR) in a direction opposite to zero (X) with rising display values, and the control (50) then controls the control signal in such a way that the pointer (20) is reset to the waiting point (0w) in the zero setting direction (X), which results in the pointer (20) at the waiting point (0w) being ready; andthe control (50) performs the return control before zero reserve control; andan update device (50) to update the zero point (00) based on the induction voltage recorded by the recording device (50) during the zero reserve control conducted by the control device (50).
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