摘要 |
An electric power assisted steering system (10) for a vehicle com prises a steering gear (12) having a rack bar (26) and a housing (24). The rack bar (26) is movable linearly relative to the housing (24) for turning steerable wheels (34 and 36) of the vehicle. An electric motor (14) is coupled with the rack bar (26) of the steering gear (12). Energization of the electric motor (14) causes linear movement of the rack bar (26) relative to the housing (24). At least one vehicle condition sensor senses a vehicle condition and generates a signal indicative of the vehicle condition. A motor current sensor (22) senses an actual current of the electric motor (14) and generates a signal indicative of the actual motor current. A single integrated circuit (16) includes a main processor (64) and a monitoring processor (66). The main processor (64) controls the actual motor current delivered to the electric motor (14). The monitoring processor (66) determines if the main processor (64) is properly functioning. |