| 摘要 |
A method and apparatus for detecting the proper functioning of an ABS control unit which utilizes dual programmed microprocessors, the second of which calculates mismatched wheel speed and both of which calculate extended control loop time. When computed wheel velocities are above 10 mph, the second microprocessor determines whether the difference in computed wheel velocity between the two microprocessors is at least 2 mph. If the difference is more than 2 mph for more than 6 consecutive program loops, a mismatched wheel speed calculation error is identified. Each of the microprocessors also compares its loop timing with the loop timing of the other microprocessor and if more than 1 millisecond late for 6 consecutive program loops, the proper diagnostic response is to set an ignition latch code which triggers an inhibit signal. In addition, if the first microprocessor determines more than a 16 millisecond delay, then the first microprocessor is reset. If the second microprocessor determines more than a 65 millisecond delay, then the second microprocessor is reset. |
