The Technical Definition: The engine computer (PCM) is failing to receive the data message regarding wheel distance and vehicle speed from the Anti-Lock Brake System (ABS) module over the CAN bus network.

Common Symptoms: The ABS and Traction Control warning lights will illuminate. The speedometer may fluctuate wildly or sit at zero, and the cruise control will be entirely disabled.

Typical Fix: Because the ABS module calculates this distance using the wheel speed sensors, diagnosing a faulty wheel speed sensor (especially the rear ones) is the most common first step. If the sensors are good, inspect the wiring harness connecting to the ABS module for corrosion or a weak battery causing network dropouts.