BYD Song Plus ABS Light? Why Your Wheel Speed Sensor Might Be the Culprit

Understanding the ABS Warning Light on Your BYD Song Plus

If the ABS light stays on continuously in your BYD Song Plus, it means the Anti-lock Braking System has detected a fault. The most common culprit is a wheel speed sensor malfunction. These sensors monitor each wheel's rotation and send data to the ABS module. When a sensor fails—due to dirt, damage, or wiring issues—the system disables ABS and triggers the warning light.

Which Sensors to Check First

Start with the front wheel speed sensors, as they are more exposed to road debris and moisture. Here’s what to inspect:

• Sensor tip: Look for metal shavings, mud, or ice buildup that can block the magnetic signal.
• Wiring harness: Check for cuts, chafing, or corrosion near the strut or wheel well.
• Tone ring: A cracked or missing tooth on the ring (attached to the axle) can also cause readings to drop out.
• Connector: Ensure the plug is fully seated and free of moisture or bent pins.

You can use a multimeter to measure the sensor's resistance (typically 1–2 kΩ) or an oscilloscope to observe the AC voltage signal while spinning the wheel. A missing or erratic signal points directly to that sensor.

Is It Safe to Drive?

You can drive short distances with the ABS light on—your conventional brakes still work normally. However, you will lose ABS functionality, meaning the wheels may lock up during hard braking, especially on slippery roads. Do not drive if the red brake warning light also comes on, as that indicates a separate hydraulic issue. For safety, have the sensor diagnosed and replaced soon. Driving without ABS increases stopping distances and reduces control in emergencies.

This material is AI-generated and for informational purposes only — it does not replace an in-person diagnosis by a qualified mechanic.