2007 Cadillac CTS Owner's Manual - Page 196

If, after several seconds, all status indicator lights remain on, or if there are no lights at all, there may be a problem with the lights or the passenger sensing system. See your dealer for service. 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. For more information see DIC Warnings and Messages on page 228. {CAUTION: If the off indicator and the airbag readiness light ever come on together, it means that something may be wrong with the airbag system. If this ever happens, have the vehicle serviced promptly, because an adult-size person sitting in the right front passenger seat may not have the protection of the frontal airbag. See Airbag Readiness Light on page 192. 196