The ABS sensor is part of the Anti-lock Brake System. It’s located on the tires and monitors the wheel speed on your car or truck. This sensor works in tandem with the electronic control module, to keep your wheels from locking up during braking.
Ask your service advisor to check your ABS wheel sensor when doing a routine brake service. However, if your ABS warning light is on, make sure to have the sensors checked right away. If the ABS sensor does not work correctly, your Anti-Lock Brake system will not be there in an emergency.
Ignoring a faulty ABS sensor will cause bigger problems with the electronic control module and the whole Anti-lock braking system might need to be replaced.
From a safety standpoint, a broken ABS sensor will decrease your ability to stop in an emergency, endangering your life, and those of others. However, there is no environmental impact of an ABS wheel sensor replacement.