How to Test an ABS Wheel Speed Sensor with a Multimeter
The ABS light is on. The car brakes erratically. You’ve scanned the codes, and they point to the “Front Left Wheel Speed Sensor.”
Instead of throwing a $60 part at it, confirm it’s bad with a simple multimeter test.
Types of ABS Sensors
There are two main types of wheel speed sensors. You must know which one you have before testing:
This guide focuses on the common 2-wire inductive sensor found on most older and many modern vehicles.
Step 1: Resistance Test (Ohms)
1. Unplug the sensor connector.
2. Set your multimeter to Ohms (Ω).
3. Touch the probes to the two pins on the sensor side.
4. Reading:** Most sensors should read between **800 to 1,500 Ohms.
5. 0.0L or Infinite:** Open circuit (broken wire inside sensor). **Replace.
6. 0.0 Ohms:** Short circuit. **Replace.
Step 2: AC Voltage Test (Spin Test)
1. Set your multimeter to AC Volts (~).
2. Connect the probes to the sensor pins.
3. Spin the wheel by hand as fast as you can.
4. Reading:** The sensor generates AC voltage as the reluctor ring passes it. You should see at least **0.2V to 0.5V AC.
5. If you see no voltage, check the reluctor ring for rust or damage before replacing the sensor.
Conclusion
Testing takes 5 minutes. If the sensor passes both tests, your problem is likely in the wiring harness or the ABS module, not the sensor itself.
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