What color light indicates a vehicle's ABS is not working? Do you currently have car insurance? Insurance is mandatory to drive in Ohio Yes I have insurance. But please show me your best quotes. No, please help me find the best insurance. Question What color light indicates a vehicle's ABS is not working? Answers Green Blue Yellow Explanation On vehicles with Anti-Lock Braking Systems (ABS), yellow malfunction lamps alert the driver to ABS malfunction. This questions appears in the following tests: Alaska Class A Knowledge Test Alaska Air Brakes Arkansas Class A Knowledge Test California Air Brakes Florida Double Iowa Air Brakes Kentucky Class A Knowledge Test Kentucky Air Brakes Louisiana Air Brakes Michigan Class B Knowledge Test Michigan Air Brakes Montana Class B Knowledge Test Montana Air Brakes Nevada Class B Knowledge Test New Mexico Class B Knowledge Test New Mexico Air Brakes Ohio Air Brakes Oklahoma Class B Knowledge Test Rhode Island Class B Knowledge Test Rhode Island Air Brakes Tennessee Air Brakes Virginia Air Brakes