2004 Cadillac CTS-V Owner's Manual - Page 161

Charging System Light When you turn the key to ON or START, this light will come on briefly to show that the generator and battery charging systems are working properly. If this light stays on, your vehicle needs service. You should take your vehicle to the dealer at once. To save your battery until you get there, turn off all accessories. Brake System Warning Light Your vehicle's hydraulic brake system is divided into two parts. If one part isn't working, the other part can still work and stop you. For good braking, though, you need both parts working well. If the warning light comes on, there is a brake problem. Have your brake system inspected right away. United States Canada This light should come on briefly when you turn the ignition key to ON. If it doesn't come on then, have it fixed so it will be ready to warn you if there's a problem. 3-39