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Code 24, Left Rear Speed Sensor

  1. Turn ignition off. Unplug ABS/AWD control unit. Using a DVOM, measure speed sensor resistance between pins No. 44 and 45 of ABS/AWD control unit wiring harness. Sensor resistance should be 600-1600 ohms.
  2. If resistance is incorrect, check wiring harness between ABS/AWD control unit and left rear speed sensor (including pins/connectors). If circuit is okay, replace speed sensor.
  3. If resistance is correct, check speed sensor voltage signal at plugs (close to clutch and brake hose on transmission and on left rear trailing arm). Connect oscilloscope to speed sensor side.
  4. Depending on oscilloscope, select special input or secondary image display. Turn left front wheel by hand, at about one revolution per second.
  5. Oscilloscope should display of 2 volts, as measured peak to peak. If voltage signal is incorrect, ensure speed sensor air gap is correct. Ensure wheel bearing or pulse wheel is not damaged or corroded. Repair as necessary.
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