This bulletin applies to 2014-2017 Chevy Corvettes. The ABS, Service Traction Control System and/or Service Stabilitrak telltale lights may be on. During initial scan for EBCM module DTCs, you may find one or more DTC C0035-C0050 with specific symptom bytes 18, 5A, 0F.
You may notice a brief and intermittent noise, click, ratchet, grind or ABS pump motor noises typically heard from inside the vehicle at parking lot speeds. A flashing Traction Control or Stabilitrak telltale may be evident at low speeds. These conditions may be caused by single or multiple pieces of ferrous metallic debris stuck to the wheel speed sensor magnetic encoder ring. Inspect and clean debris from the encoder ring.
Some newer models have begun to use a different type of wheel speed sensor encoder ring or tone wheel. Instead of a traditional mechanical type tooth tone wheel, the wheel speed sensor tone wheel is now made of a magnetized nitrile rubber ring, typically brown in color. The magnetic ring consists of multiple north and south pole pairs surrounding the outer circumference.
When this magnetic ring rotates and passes by the wheel speed sensor head, it generates a sign wave in the sensor. The sensor converts an analog signal to a digital square wave. Typical digital signal values switch between 7mA (low) and 14mA (high) DC current.
Do not use any type of magnetic tool to remove debris from the bearing magnetic encoder. To properly clean the magnetic encoder ring, some applications may require removal of the bearing/hub assembly. Use a dry nylon soft bristle brush. If debris still remains, wash the encoder ring with a mild soap detergent and wipe dry.