DTC 15 - Faulty Wheel Speed Sensor Output

NOTE: If after all testing procedures have been completed system is not functioning properly, substitute ECU with known-good unit and retest.

1. This DTC normally is set when other wheel speed sensor DTCs are set. Test each sensor. See WHEEL SPEED SENSOR TESTING  . If all sensor voltages and resistances are within specification, go to next step. Replace any malfunctioning sensor. See WHEEL SPEED SENSOR R & I  .
2. Check each wheel speed sensor-to-rotor gap. See WHEEL SPEED SENSOR  under ADJUSTMENTS. If all gaps are within specification, go to next step. If any gaps are not within specification, adjust sensor-to-rotor gap or replace senor.
3. Inspect all wheel speed sensor rotors for damaged and missing teeth. Replace any damaged rotors. Using an oscilloscope, check waveform patterns. See Fig 1 . If all rotors are okay, replace ECU and road test vehicle. Ensure DTC does not reset.

Fig 1: Identifying Abnormal ABS Rotor Waveform Patterns

Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.