Lights that indicate that anti-lock brakes are not working are: Question Lights that indicate that anti-lock brakes are not working are: Answers Gray. Blue. Yellow. Explanation Vehicles equipped with Anti-Lock Braking Systems (ABS) have yellow malfunction lights to indicate issues in the braking system. This questions appears in the following tests: Alaska Air Brakes Arizona Class A Knowledge Test Arizona Air Brakes Hawaii Air Brakes Hawaii Air Brakes Idaho Class A Knowledge Test Maine Class B Knowledge Test Maryland Class B Knowledge Test Michigan Class B Knowledge Test Mississippi Class B Knowledge Test Oklahoma Air Brakes Rhode Island Air Brakes Tennessee Air Brakes Virginia Class B Knowledge Test Washington Double Wisconsin Class B Knowledge Test
