ABS Light On. 1999 Ford F53 V10.
Known info: most likely cause: bad differential abs sensor.
No other dash lights on, no codes on OBD scanner. I do not have abs scanner.
ABS fuse checked. OK
Brake fluid level checked. OK
Visual inspection of all sensor wiring. Looked good.
Left front front abs sensor checked for continuity using a multimeter. I have no spec on sensor. Also checked using oscilloscope, nice looking sine wave displayed on screen. Sensor and connector removed, cleaned and replaced.
Right front front abs sensor checked for continuity using a multimeter. I have no spec on sensor. Checked using oscilloscope, Sine wave displayed on screen. Sensor and connector removed, cleaned and replaced.
Resistance for the left and right front sensor were within 300 ohms of each other.
Abs light still on.
Removed rear abs sensor. Check resistance with meter, showed 3 millions ohm and climbing. This reading makes no sense because this is also the speed sensor. The speedometer works fine.
Left the sensor disconnected and took the RV for a drive. The speedometer still works fine. No codes on OBD scanner.
I ordered a new sensor online.
Started researching and found an article that said the rear and/or front abs sensor can be used as a speed sensor. Which explains why the speedometer still works.
Replaced rear abs sensor.
ABS light still on.
Took RV for a drive, after 200 feet the ABS light when out and stayed that way
Linear Mode
