C065F Left Rear Wheel Speed Sensor B Circuit/Open
C065F reports that the second speed channel at the left rear wheel has no closed circuit. No carmaker publishes this code and no service bulletin mentions it, so the exact test is unknown. With active sensors an open is easy to recognise: NXP's KMI25 draws a constant base current of about 7 mA through the same two wires that carry its speed pulses, so a broken lead or a loose plug leaves the module with no current at all. A Motor magazine test on Honda sensors found 10 to 11 V supplied by the ABS unit and stressed that the sensor goes silent once that feed is lost, which is why the supply is checked before the sensor is condemned. As long as sensor A still works, ABS normally carries on; functions that need the second signal are withdrawn.
Likely causes
Symptoms
- Warning for brake or driver assistance system right after switching on
- Functions relying on the second rear left signal not available
Repair estimate
Typical range across vehicles; the real cost depends on what the testing finds.