Rick's Free Auto Repair Advice

C1230 ABS light on Ford

Diagnose and fix C1230 ABS light on Ford

If you have a C1230 ABS light on Ford issue, follow these test procedures to diagnose and fix the problem. The trouble code C1230 refers to a Wheel Speed Sensor Rear Center Input Circuit Failure. Notice that it says CIRCUIT failure. It does not say SENSOR failure, although the sensor may be causing the problem, you should test the circuit BEFORE replacing the sensor.

Test rear differential speed sensor wiring

The rear center wheel speed sensor is located on the rear differential. Using a digital DVOM meter, BACKPROBE the light green/red and light green/black wires to the sensor with the key in the ON position (engine off). Connect your meter BEFORE turning the key to ON because the voltage may only appear for a split second, especially if there’s an open condition in the sensor wiring. Your voltage reading should be more than 9-volts.

If you don’t see 9-volts, check the integrity of the

C1230 ABS light on Ford

Rebuilt ABS module form modulemaster.com

light green/red and light green/black wires between the sensor connector and the ABS module. Check for continuity, opens and high resistance, short to ground or short to power. Repair the harness as necessary. If the harness tests good but you see less than 9-volts, replace the ABS module with a rebuilt unit. The replacement unit must be programmed to the vehicle, so don’t buy a junkyard unit. Buy from a reputable rebuilder and have them program the unit to your exact VIN number.

If you see more than 9-volts across the wires, C1230

C1230 ABS light on Ford

Ford #6L3Z9E731A rear differential sensor

ABS light on Ford indicates a faulty differential speed sensor. Replace the differential speed sensor

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Posted on by Rick Muscoplat

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