Seat Belt Systems: Description and Operation

The automatic safety belt utilizes an upper-torso belt, a lap belt and two retractor assemblies mounted to each front door. The belt assemblies are permanently buckled to fixed hasps mounted near the vehicle's central console.
When a front door is opened, the corresponding safety belt retractor switch is closed and battery voltage is applied to the Safety Belt Shoulder and Lap Retractor Solenoids through the Safety Belt Indicator Driver Module. The Lap Retractor Solenoids are energized and restrain the safety belt retractor lock pendulums.
The operation of the Retractor Switch results in a voltage across the Safety Belt Indicator Driver Module, which serves as a relay for the Fasten Belts Indicator. The voltage energizes the coil and closes the contacts which apply battery voltage from Fuse 16 to the Indicator. The diode in the Safety Belt Indicator Driver Module limits the voltage across the coil so that there will be sufficient voltage to operate the solenoids.
When the door is closed, the corresponding Safety Belt Retractor Switch is opened. The Time Delay Module keeps the solenoids energized for approximately one second after the Safety Belt Retractor Switch is opened. The Safety Belt Indicator Driver Module and Retractor Solenoids then de-energize. The indicator light goes out and the Safety Belt Retractors are then allowed to lock up in the event of sudden deceleration.
Voltage is applied at all times to terminal A of the Safety Belt Indicator Driver Module. Voltage is also applied to terminal D when the ignition switch is on Run, Bulb Test or Start.