Seat Belt Control Module: Description and Operation

Passive Restraint System Inputs:

The following description applies to the operation of the passive restraint system. The provided chart indicates the system inputs and pins necessary for the application to the driver's and passenger's side of the system.

Conditions To Move The Carrier From The Front Body Pillar To The Center Body Pillar
To move the front seat shoulder strap carrier from the front body pillar (A-pillar) to the center body pillar (B-pillar) when the front door is closed (Pin 13 floating/not grounded) and the ignition switch is in the ON position (Pin 25 battery voltage), the passive restraint control module will check the B-pillar limit switch (Pin 18).

If the B-pillar limit switch is not activated (Pin 18 floating/not grounded) the passive restraint control module will apply power to the safety belt retractor motor. This will send the front seat shoulder strap carrier from the front body pillar (A-pillar) to the center body pillar (B-pillar) (Pins 2 and 17 battery voltage, Pins 3 and 4 grounded), until the B-pillar limit switch is activated (Pin 18 grounded).

If the B-pillar limit switch is activated (Pin 18 grounded), no action will occur.

Conditions to Move the Carrier From the Center Body Pillar to the Front Body Pillar
To move the front seat shoulder strap carrier from the center body pillar (B-pillar) to the front body pillar (A-pillar) when the front door is opened (Pin 13 grounded) and the inertia fuel shutoff switch is set (Pin 12 floating), the passive restraint control module will check the A-pillar limit switch (Pin 5).

If the A-pillar limit switch is not activated (Pin 5 floating), the passive restraint control module will apply power to the safety belt retractor motor. This will send the front seat shoulder strap carrier from the center body pillar (B-pillar) to the front body pillar (A-pillar) (Pins 3 and 4 high, Pins 2 and 17 grounded), until the A-pillar limit switch is activated (Pin 5 grounded).

If the A-pillar limit switch is activated (Pin 5 grounded), or the inertia fuel shutoff switch is tripped (Pin 12 grounded), no action will occur.

Conditions to Activate the Safety Belt Warning Indicator
When the passive restraint control module determines a safety belt warning is required, the safety belt warning indicator output (Pin 16) supplies a ground to the safety belt warning indicator. This action activates the safety belt warning indicator.

When the ignition switch is in the ON position (Pin 25 high), and both the LH and RH B-pillar limit switches are not activated (Pin 18 or 21 floating/not grounded), the safety belt warning indicator output is activated (Pin 16 grounded).

The safety belt warning indicator is also activated when the ignition switch is in the ON position (Pin 25 battery voltage) and either of the shoulder belts are retracted in (Pin 14 or 15 floating/not grounded).

NOTE: The safety belt warning chime works with the safety belt warning indicator.

Conditions to Activate the Safety Belt Warning Chime
When the passive restraint control module determines that a warning is required, the audible safety belt warning chime output (Pin 1) supplies a ground to the safety belt warning chime through the timer module. When the ignition switch is in the ON position (Pin 25 battery voltage), and either the RH front center safety belt retractor or the LH front center safety belt retractor is retracted in (Pin 14 or 15 floating/not grounded), the safety belt warning chime output is activated (Pin 1 grounded) for five seconds. If this output has been triggered and timed out, it can be triggered again by retracting in the other front center safety belt retractor (floating/grounding Pin 14 or 15).