Code 6, Wheel Speed Sensor Signal Changed Rapidly
- Turn ignition off. Disconnect RWAL EBCM connector. Check resistance between EBCM terminals No. 16 and 17 while wiggling harness between sensor and EBCM. See Fig 1
. If reading is not 1000-2000 ohms and steady, go to step 4).
- If reading is 1000-2000 ohms and steady, remove speed sensor from rear differential case. Inspect tip of sensor for metal particles. If metal particles are present, replace sensor, and go to next step.
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- Inspect exciter ring through sensor hole in differential case. Rotate exciter ring and check for damaged teeth and lateral runout. If exciter ring is damaged or lateral runout is present, replace exciter ring. If no faults are found, go to step 6).
- If resistance between terminals No. 16 and 17 of RWAL EBCM connector is not 1000-2000 ohms and steady, disconnect speed sensor connector. Measure resistance across sensor connector terminals. If resistance is 1000-2000 ohms, repair open or short in White or Orange wire between RWAL EBCM and speed sensor.
- If resistance is greater than 2000 ohms or less than 1000 ohms, replace wheel speed sensor. After replacing sensor, verify speed sensor signal by using procedure described in steps 6) and 7).
- Install speed sensor, and connect connector. Reconnect RWAL EBCM connector. Raise vehicle, and support with rear wheels off of floor. If vehicle is 4WD, ensure vehicle is in 2H mode. Start engine, and drive vehicle faster than 20 MPH. Backprobe RWAL EBCM terminals No. 16 and 17 using a 10-megohm DVOM on AC-volts scale.
- If voltage reading is greater than 650 millivolts and steady, replace RWAL EBCM. If voltage reading is less than 650 mV or is erratic, replace wheel speed sensor.