When changing front wheel bearing do you also have to replace the abs sensor make warning light go out?

No, you don't automatically have to replace the ABS sensor when changing a front wheel bearing, even if the ABS warning light is on. However, the ABS sensor is often located very near the wheel bearing, and it's possible to damage it during the bearing replacement.

Here's why you might consider replacing the ABS sensor:

* Accidental Damage: The ABS sensor is a delicate component. If it's bumped, scraped, or otherwise mishandled during the bearing replacement, it can become damaged and malfunction, triggering the ABS light.

* Pre-existing Issue: The ABS light might have been on *before* you started the bearing replacement. The faulty bearing might have been causing vibrations that affected the sensor, or the sensor itself might have been failing independently. Replacing the bearing might not solve the ABS light problem if the sensor is already bad.

In short: It's not mandatory, but it's *prudent* to inspect the ABS sensor carefully during the wheel bearing replacement. If it shows any signs of damage (broken wires, scratches, etc.), it's best to replace it to avoid future problems. If the ABS light remains on after the bearing replacement, you'll likely need to diagnose and fix the ABS sensor separately.