2010 Cadillac CTS Owner's Manual - Page 136

4-26 . Instruments and Controls The vehicle will not pass this inspection if the OBD II (on-board diagnostic) system determines that critical emission control systems have not been completely diagnosed by the system. The vehicle would be considered not ready for inspection. This can happen if the battery has recently been replaced or if the battery has run down. The diagnostic system is designed to evaluate critical emission control systems during normal driving. This can take several days of routine driving. If this has been done and the vehicle still does not pass the inspection for lack of OBD II system readiness, your dealer/retailer can prepare the vehicle for inspection. Brake System Warning Light This vehicle's hydraulic brake system is divided into two parts. If one part is not working, the other part can still work and stop the vehicle. For good braking both parts need to be working well. If the warning light comes on, there is a brake problem. Have the brake system inspected right away. When the ignition is on, the brake system warning light will also come on when the parking brake is set. The light will flash or stay on if the parking brake is not fully released. If the light stays on after the parking brake is fully released there is a base brake problem. { CAUTION The brake system might not be working properly if the brake system warning light is on. Driving with the brake system warning light on can lead to a crash. If the light is still on after the vehicle has been pulled off the road and carefully stopped, have the vehicle towed for service. United States Canada This light should come on briefly when the ignition is placed in ON/RUN. If it does not come on then, have it fixed so it will be ready to warn if there is a problem.