1997 Ford Aerostar Owner's Manual - Page 129

u and the electrical wiring which connects the components. The diagnostic module monitors its own internal circuits and the supplemental air bag electrical system readiness (including the impact sensors), the system wiring, the air bag system readiness light, the air bag backup power and the air bag igniters. Determining if System Is Operational The Air Bag Supplemental Restraint System uses a readiness light and a tone to indicate the condition of the system. The readiness light is in the instrument cluster. When you turn the ignition key to ON, this light will illuminate for approximately six (6) seconds and then turn off. This indicates that the system is operating normally. NOTE: Routine maintenance of the air bag system is not required. A problem with the system is indicated by one or more of the following: u the readiness light will either flash or stay lit, u the readiness light will not light immediately after ignition is turned on, u a group of five beeps will be heard. The tone pattern will repeat periodically until the problem and light are repaired. If any of these things happen, even intermittently, have the Air Bag Supplemental Restraint System serviced at your Ford or Lincoln-Mercury dealer immediately. Unless serviced, the system may not function properly in the event of a collision. 127