Mitsubishi Eclipse II technical information manual page 260

text version of content this owner's manual page from owners manual to the vehicle Mitsubishi Eclipse, year of production 1995 - 1999:

DRIVE-CONTROL COMPONENTS - ABS DIAGNOSIS OF THE WHEEL SPEED SENSOR SYSTEM On-board diagnosis of the wheel speed sensor sys-is detectable only when the vehicle is put into motion or when it is running. Ltern is accomplished by executing the diagnostic program stored in the computer. U&g the program, (2) Hardware failure detection the ABS-ECU monitors each wheel speed sensor The ABS-ECU monitors the sensors, harness, system (wheel speed sensor, rotor, etc.) to detect etc. by using its open/short circuit monitoring a failure. In addition, the ABS-ECU monitors a short circuit and voltage monitoring program to detect or open circuit in the sensor system by using its a failure such as an open or short circuit. A voltage monitoring circuit and voltage monitoring program. major feature of the open/short circuit monitoring circuit is that an open or short circuit failure The former is called “software failure detection”, is always detectable (even when the vehicle whereas the latter is called “hardware failure detec- tion”. is stationary). (1) Software failure detection When the vehicle is in motion, however, a failure may be detected by software failure detection In this diagnostic test mode, the speeds of thefunction before the same open or short circuit four wheels calculated from the sensor outputs failure is detected by the hardware failure detec- are compared. If there is any sensor systemtion function. Such a situation may occur de- that outputs an abnormal speed or an abnormalpending on the condition of vehicle and the decelerated speed, the ABS-ECU determines nature of the failure. that the system is out of order. Such a failure FAIL-SAFE FUNCTION the ABS warning light to light, drives the valve Should a failure occur in the ABS system, theABS- ECU isolates the system to retain the vehicle’s ordi- relay to interrupt control of the solenoid valves nary braking function, thus assuring a high measurein the HU, and restores the ordinary braking of safety. mode. Ll If the ABS-ECU determines that the system is defective as the result of diagnosis, it causes DIAGNOSTIC FUNCTIONS To facilitate inspection of the ABS system, the ABS-the vehicle must be stopped, and the ignition should ECU offers the following facilities: be OFF. The ABS scan tool mode is entered when you select l Diagnostic trouble code output and erasure l Data list output the ABS system on the scan tool. In this mode, l Actuator tests diagnostic output, data list output and actuator test functions are available. During an actuator test, how- All of the items described above can be checked by the scan tool. ever, the ABS warning light illuminates and anti-lock Scan Tool - ABS Interface control is inhibited to prevent ABS operation when a brake is temporarily inactivated during the actuator The scan tool function is entered by connectingtest. the scan tool to the data link connector. At this time, Scan tool 0 Wheel speeds of 0 km/h (0 mph), parkedcondi- mode entry tion condition 0 Check harness of scan tool connected to data link connector of vehicle 0 ABS system selected by control switch of scan tool (Specified serial data received) NOTE No communications with the ABS-ECU can be made by con- necting the scan tool while the vehicle is in operation [wheel speeds not 0 km/h (0 mph)]

owners manual Mitsubishi Eclipse

owners manual Mitsubishi Eclipse - year of production: 1995, 1996, 1997, 1998, 1999 - Mitsubishi Eclipse II technical information manual EN