Speedometer Not Working on a 2004 Ford F-250 Super Duty

This video shows how we diagnosed a non-working speedometer on a 2004 Ford F-250 Super Duty. A C1230 Wheel Speed Sensor Rear Center Input Circuit Code in the ABS unit led us the the rear differential speed sensor. Visual inspection of the sensor and the wiring harness attached to it found a nicked wire with heavy corrosion. The wire was repaired which solved the problem and the speedometer worked again.

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