Seat Belt System Buick Century VI

Fastener Tightening Specifications

FASTENER TIGHTENING SPECIFICATIONS

Scheme 1

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Diagnostic Starting Point - Seat Belts

Begin the system diagnosis by reviewing the SEAT BELT SYSTEM DESCRIPTION AND OPERATION . Reviewing the description and operation information will help you determine the correct symptom diagnostic procedure when a malfunction exists. Reviewing the description and operation information will also help you determine if the condition described by the customer is normal operation.

Refer to SYMPTOMS - SEAT BELTS in order to identify the correct procedure for diagnosing the system and where the procedure is located.

Operational and Functional Checks

Perform the following inspection from the driver seat

1. Turn the ignition switch to the ON position. Verify proper operation of the seat belt reminder lamp with the belt buckled and with the belt unbuckled. Refer to «SEAT BELT SYSTEM DESCRIPTION AND OPERATION»(/buick/century/vi-1997-2005/remont/restraints-control-systems/#seat-belt-system) .
2. Inspect the shoulder belt guide in order to ensure that the following conditions are met: The shoulder belt guide swivels freely. The seat belt webbing is seated flatly in the guide slot. The seat belt webbing does not bind.
3. Verify that the seat belt buckle faces inboard and is accessible.
4. Verify that the seat belt retractor units are securely attached.
5. Verify that the seat belt anchor bolts are secure.
6. Fully extend the seat belt webbing. Verify that the seat belt webbing does not have any twists or tears.
7. Allow the seat belt webbing to retract. Verify that the seat belt webbing returns freely and completely back into the retractor.
8. Snap the seat belt latch plate into the buckle.
9. Sharply tug on the seat belt latch plate and the buckle. Verify that the seat belt latch plate and the buckle remain locked when tugged.
10. Push the button on the buckle. Verify that the seat belt latch plate releases easily from the buckle. Verify that the button returns to its original position.

Repeat the inspection procedure, steps 2-10, from the front passenger seat.

Perform the following steps in order to inspect the center seat belts

1. Verify that the center seat belts are accessible.
2. Verify that the center seat belts have no twists or tears in the webbing.
3. Snap the center seat belt latch plate into the buckle.
4. Sharply tug on the seat belt latch plate and the buckle. Verify that the seat belt latch plate and the buckle remain locked when tugged.
5. Push the button on the buckle. Verify that the seat belt latch plate releases easily from the buckle. Verify that the button returns to its original position.

Repeat the inspection procedure, steps 2-10, from the rear seats.

Repeat the center seat belt inspection procedure, steps 1-5, from the rear seat.

For information on removal of the rear seats cushions refer to SEAT CUSHION REPLACEMENT - REAR .

Emergency Locking Retractors

Scheme 4

1. Fasten the seat belts, an assistant is needed when the retractor under test is not part of the driver seat belt.
2. Accelerate the vehicle slowly to 16 km/h (10 mph) and apply the brakes firmly.
3. Verify that the seat belt locks when braking firmly.
4. If the belt does not lock, proceed with the following steps. 4.1. Remove the seat belt retractor assembly. 4.2. Tilt the seat belt retractor slowly. 4.3. Ensure that the seat belt webbing can be pulled from the retractor at an inclination of 15 degrees or less and cannot be pulled from the retractor at an inclination of 45 degrees or more. 4.4. If the seat belt retractor does not operate as described, replace the retractor assembly. «SEAT BELT RETRACTOR REPLACEMENT - LEFT FRONT»(/buick/century/vi-1997-2005/remont/restraints-control-systems/#seat-belt-system) «SEAT BELT RETRACTOR REPLACEMENT - RIGHT FRONT»(/buick/century/vi-1997-2005/remont/restraints-control-systems/#seat-belt-system) «SEAT BELT RETRACTOR REPLACEMENT - REAR»(/buick/century/vi-1997-2005/remont/restraints-control-systems/#seat-belt-system)

Symptoms - Seat Belts

Visual/Physical Inspection

1. Inspect for aftermarket devices which could affect the operation of the seat belt system. Refer to CHECKING AFTERMARKET ACCESSORIES in Wiring Systems.
2. Inspect the easily accessible or visible system components for obvious damage or conditions which could cause the symptom.

Intermittent

Faulty electrical connections or wiring may be the cause of intermittent conditions. Refer to TESTING FOR INTERMITTENT AND POOR CONNECTIONS in Wiring Systems.

Symptom List

Refer to the following symptom diagnostic procedure in order to diagnose the symptom

SEAT BELT INDICATOR CIRCUIT MALFUNCTION

Seat Belt Indicator Circuit Malfunction

SEAT BELT INDICATOR CIRCUIT MALFUNCTION

Seat Belt Service Precautions

1. Do not bleach or dye the seat belt webbing. Clean the seat belt webbing only with a mild soap and water solution and a soft brush or cloth.
2. Keep sharp edges and damaging objects away from the seat belts. Avoid bending or damaging any part of the seat belt buckle or latch plate.
3. Replace any seat belts which are cut or damaged in any way.
4. Use only correct seat belt anchor bolts and screws. Tighten the bolts and the screws to the correct torque value. Refer to «FASTENER TIGHTENING SPECIFICATIONS»(/buick/century/vi-1997-2005/remont/restraints-control-systems/#seat-belt-system__fastener-tightening-specifications) . When installing the seat belt anchor bolts, start the bolt by hand in order to ensure that the bolt is threaded correctly.
5. Some seat belts and retractors must be serviced as a set with service replacement parts only. Do not attempt to make repairs to the individual components which are only serviced as a set.
6. Verify that the replacement part number is correct for the vehicle at that seating position. Do not substitute a seat belt from a different seating position.

Repairs and Inspections Required After a Collision

After a minor collision where no automatic restraint device was deployed, seat belt system replacement may not be necessary, unless some of the parts are torn, worn, or damaged.

Scheme 5

1. Position the left front seat to the forward position.
2. Remove the nut from the seat belt buckle.
3. Disconnect the electrical connector.
4. Remove the seat belt buckle from the left front seat.

Scheme 6

1. Install the seat belt buckle to the left front seat.
2. Connect the electrical connector.
3. Install the seat belt buckle nut. Tighten Tighten the seat belt buckle nut to 42 N.m (31 lb ft).
4. Position the left front seat to the original position.

Scheme 7

1. Remove the front seat. Refer to SEAT REPLACEMENT - SPLIT BENCH in Seats. IMPORTANT: When drilling out the rivet do not enlarge the rivet hole.
2. Drill out the rivet that retain the seat belt buckle to the rear of the front seat track using a 1/4 inch (6.35 mm) drill bit.
3. Remove the seat belt buckle from the front seat track.

Scheme 8

1. Install the seat belt buckle to the front seat track. IMPORTANT: The rivet is only used for installation alignment.
2. Install the new rivet to secure the seat belt buckle to the rear of the front seat track.
3. Install the front seat. Refer to SEAT REPLACEMENT - SPLIT BENCH in Seats .

Scheme 9

1. Position the right front seat to the forward position.
2. Remove the nut from the seat belt buckle.
3. Remove the seat belt buckle from the right front seat.

Scheme 10

1. Position the seat belt buckle to the right front seat.
2. Install the seat belt buckle nut. Tighten Tighten the seat belt buckle nut to 42 N.m (31 lb ft).
3. Position the right front seat to the original position.

Scheme 11

1. Remove the front seat. Refer to SEAT REPLACEMENT - SPLIT BENCH in Seats. IMPORTANT: When drilling out the rivet do not enlarge the rivet hole.
2. Drill out the rivet that retain the seat belt to the rear of the front seat track using a 1/4 inch (6.35 mm) drill bit.
3. Remove the seat belt from the front seat track.

Scheme 12

1. Install the seat belt to the front seat track. IMPORTANT: The rivet is only used for installation alignment.
2. Install the new rivet to secure the seat belt to the rear of the front seat track.
3. Install the front seat. Refer to SEAT REPLACEMENT - SPLIT BENCH in Seats.

Scheme 13

1. Remove the rear seat cushion. Refer to SEAT CUSHION REPLACEMENT - REAR in Seats.
2. Remove the center seat belts nuts (1).
3. Remove the center seat belts from the vehicle.

Installation Procedure

Scheme 14

1. Install the center seat belts to the vehicle.
2. Install the center seat belts nuts (1). Tighten Tighten the nuts to 42 N.m (31 lb ft). IMPORTANT: Be sure to route the buckle correctly through the rear seat cushion.
3. Install the rear seat cushion. Refer to SEAT CUSHION REPLACEMENT - REAR in Seats.

Scheme 15

1. Open the seat belt guide loop cover.
2. Remove the guide loop nut.
3. Remove the guide loop from the guide adjuster bracket.
4. Remove the center pillar upper trim panel. Refer to TRIM PANEL REPLACEMENT - UPPER CENTER PILLAR in Interior Trim.
5. Remove the shoulder belt guide adjuster bracket bolts.
6. Remove the shoulder belt guide adjuster bracket from the center pillar.

Scheme 16

1. Position shoulder belt guide adjuster bracket to the center pillar.
2. Install the shoulder belt guide belt adjuster bracket bolts. Tighten Tighten the shoulder belt guide adjuster bracket bolts to 42 N.m (31 lb ft).
3. Install the upper center pillar trim panel. Refer to TRIM PANEL REPLACEMENT - UPPER CENTER PILLAR in Interior Trim.
4. Install the guide loop to the guide adjuster bracket.
5. Install the guide loop nut. Tighten Tighten the guide loop nut to 42 N.m (31 lb ft).
6. Close the guide loop cover.

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Scheme 20

1. Open the seat belt guide loop cover.
2. Remove the guide loop nut.
3. Remove the guide loop from the guide adjuster bracket.
4. Remove the lower center pillar trim. Refer to TRIM PANEL REPLACEMENT - LOWER CENTER PILLAR in Interior Trim.
5. Remove the intermediate guide bolts.
6. Remove the anchor plate nut from the seat stud.
7. Remove the anchor plate from the seat stud.
8. Remove the seat belt retractor bolt.
9. Remove the seat belt retractor from the lower center pillar.

Scheme 21

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Scheme 23

Scheme 24

1. Install the belt retractor into the T-slot in the center pillar.
2. Install the seat belt retractor bolt. Tighten Tighten the seat belt retractor bolt to 68 N.m (50 lb ft).
3. Position the anchor plate to the seat stud.
4. Install the anchor plate nut to the seat stud. Tighten Tighten the anchor plate nut to 42 N.m (31 lb ft).
5. Install the intermediate guide bolts. Tighten Tighten the intermediate guide bolts to 10 N.m (89 lb in).
6. Install the lower center pillar trim. Refer to TRIM PANEL REPLACEMENT - LOWER CENTER PILLAR in Interior Trim.
7. Position the guide loop to the guide adjuster bracket.
8. Install the guide loop nut. Tighten Tighten the guide loop nut to 42 N.m (31 lb ft).
9. Close the guide loop cover.

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Scheme 28

1. Open the seat belt guide loop cover.
2. Remove the guide loop nut.
3. Remove the guide loop from the guide adjuster bracket.
4. Remove the lower center pillar trim. Refer to TRIM PANEL REPLACEMENT - LOWER CENTER PILLAR in Interior Trim.
5. Remove the intermediate guide bolts.
6. Remove the anchor plate nut from the seat stud.
7. Remove the anchor plate from the seat stud.
8. Remove the retractor side seat belt bolt.
9. Remove the retractor side seat belt from the lower center pillar.

Scheme 29

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Scheme 31

Scheme 32

1. Install the seat belt retractor into the T-slot in the center pillar.
2. Install the retractor side seat belt bolt. Tighten Tighten the retractor side belt bolt to 68 N.m (50 lb ft).
3. Install the intermediate guide bolts. Tighten Tighten the intermediate guide bolts to 10 N.m(89 lb in).
4. Position the anchor plate to the seat stud.
5. Install the anchor plate nut to the seat stud. Tighten Tighten the anchor plate nut to 42 N.m (31 lb ft).
6. Install the lower center pillar trim. Refer to TRIM PANEL REPLACEMENT - LOWER CENTER PILLAR in Interior Trim.
7. Position the guide loop to the guide adjuster bracket.
8. Install the guide loop nut. Tighten Tighten the guide loop nut to 42 N.m (31 lb ft).
9. Close the guide loop cover.

Scheme 33

Scheme 34

1. Remove the rear seat cushion and rear seat back. Refer to SEAT BACK REPLACEMENT - REAR (NON-FOLDING) or SEAT BACK REPLACEMENT - REAR (FOLDING) in Seats.
2. Remove the rear quarter upper trim panel. Refer to TRIM PANEL REPLACEMENT - REAR QUARTER UPPER in Interior Trim.
3. Remove the rear quarter lower trim panel. Refer to TRIM PANEL REPLACEMENT - REAR QUARTER LOWER in Interior Trim.
4. Remove the rear seat belt retractor anchor bolt.
5. Loosen the rear window trim panel. Refer to TRIM PANEL REPLACEMENT - REAR WINDOW SHELF in Interior Trim.
6. Remove the rear sound barrier. Refer to SOUND BARRIER REPLACEMENT - REAR SEAT BACK in Interior Trim.
7. Remove the rear seat belt retractor bolt.
8. Remove the rear seat belt retractor from the vehicle.

Scheme 35

Scheme 36

1. Install the rear seat belt retractor to the vehicle. IMPORTANT: Be sure to seat the alignment tabs.
2. Install the rear seat belt retractor bolt. Tighten Tighten the rear seat belt retractor bolt to 68 N.m (50 lb ft).
3. Install the rear sound barrier. Refer to SOUND BARRIER REPLACEMENT - REAR SEAT BACK in Interior Trim.
4. Install the rear window trim panel. Refer to TRIM PANEL REPLACEMENT - REAR WINDOW SHELF in Interior Trim.
5. Install the rear seat belt retractor anchor bolt. Tighten Tighten the rear seat belt retractor bolt to 42 N.m (31 lb ft).
6. Install the rear quarter lower trim panel. Refer to TRIM PANEL REPLACEMENT - REAR QUARTER LOWER in Interior Trim.
7. Install the rear quarter upper trim panel. Refer to TRIM PANEL REPLACEMENT - REAR QUARTER UPPER in Interior Trim.
8. Install the rear seat cushion and rear seat back. Refer to SEAT BACK REPLACEMENT - REAR (NON-FOLDING) or SEAT BACK REPLACEMENT - REAR (FOLDING) in Seats.

Scheme 37

1. Remove the rear seat back. Refer to SEAT BACK REPLACEMENT - REAR (NON-FOLDING) or SEAT BACK REPLACEMENT - REAR (FOLDING) in Seats.
2. Remove the rear center seat belts. Refer to «SEAT BELT REPLACEMENT - CENTER REAR»(/buick/century/vi-1997-2005/remont/restraints-control-systems/#seat-belt-system) .
3. Remove the bracket nut (1) located between the center seat belts.
4. Remove the bolts (2) from each end of the bracket.
5. Remove the bracket from the vehicle.

Scheme 38

1. Position the bracket in the vehicle.
2. Apply a thread sealant, GM P/N USA 12345382 Canada 10953489, Loctite 242, Permatex 24200 to the threads of the bolts (2) and also the stud for the bracket nut (1).
3. Install the bolts (2) to each end of the bracket. Tighten Tighten the child seat latch bracket bolts to 42 N.m (31 lb ft).
4. Install the bracket nut (1) between the center seat belts. Tighten Tighten the child seat latch bracket nut to 42 N.m (31 lb ft).
5. Install the rear center seat belts. Refer to «SEAT BELT REPLACEMENT - CENTER REAR»(/buick/century/vi-1997-2005/remont/restraints-control-systems/#seat-belt-system) .
6. Install the rear seat back. Refer to SEAT BACK REPLACEMENT - REAR (NON-FOLDING) or SEAT BACK REPLACEMENT - REAR (FOLDING) in Seats.

Scheme 39

1. Remove the rear shelf trim panel. Refer to TRIM PANEL REPLACEMENT - REAR WINDOW SHELF in Interior Trim.
2. Slide the sound barrier out from under the upper quarter panel trim.
3. Pull the sound barrier forward to access the tether bolts.
4. Remove the child seat tether bracket to rear shelf bolts.
5. Remove the child seat tether brackets from the rear shelf.

Scheme 40

1. Install the child seat tether brackets to the slots in the rear shelf.
2. Install the child seat tether bracket to rear shelf bolts. Tighten Tighten the child seat tether bracket to rear shelf bolts to 20 N.m (151b ft).
3. Push the sound barrier back into its original position.
4. Install the rear shelf trim panel. Refer to TRIM PANEL REPLACEMENT - REAR WINDOW SHELF in Interior Trim.

Child Shoulder Belt Guide Rerouter Replacement - Rear

Tools Required

J 38778 Door Trim Pad and Garnish Clip Remover

Scheme 41

1. Push back the rear seat back.
2. Remove the push-pin retainer from the rear shoulder belt guide using the J 38778 .
3. Remove the rear shoulder belt guide from the lower rear quarter trim panel.

Scheme 42

1. Push back the rear seat back.
2. Align the rear shoulder belt guide to the lower rear quarter trim panel.
3. Install the push-pin retainer to the rear shoulder belt guide.

Fasten Safety Belt Indicator

The IPC illuminates the fasten safety belt indicator when the following occurs

1. The body control module (BCM) detects that the driver seat belt is unbuckled. The IPC receives a class 2 message from the BCM requesting illumination. The IPC illuminates the indicator for 20 seconds and then flashes the indicator for 55 seconds. The BCM also activates an audible warning.
2. The IPC detects a loss of class 2 communications with the BCM.

Restraint System

Seat belts are the primary means of occupant restraint. Seat belts help to keep the occupant(s) inside the passenger compartment and to gradually reduce the impact forces during the following events

1. Frontal impact type crashes
2. Rear impact type crashes
3. Side impact type crashes
4. Roll-over type crashes

All seat belt retractors have emergency locks. The retractors remain unlocked during normal operation and under normal driving conditions. The retractors remain unlocked during normal conditions in order to allow free movement of the upper body of each occupant. A pendulum locks the seat belt webbing into position. The pendulum causes a locking bar to engage a cog on the spool of the retractor mechanism when the following conditions occur

1. A rapid extraction of the seat belt webbing from the retractor
2. An abrupt change in vehicle speed
3. An abrupt change in vehicle direction
4. Operation of the vehicle on a steep upgrade
5. Operation of the vehicle on a downgrade

The seat belts have an automatic locking (cinch) feature. The cinch feature is activated when the seat belt webbing is completely extended from the retractor. The cinch feature prevents the webbing from extending beyond the position from which it is allowed to retract. Use of the cinch feature is recommended for securing a child seat. The cinch feature may be cancelled by allowing the webbing to wind back completely into the retractor. After the cinch feature is cancelled, the webbing is unlocked. After the cinch feature is cancelled, the webbing will extend from the retractor. This vehicle is also equipped with a supplemental inflatable restraint (SIR) system. Refer to SIR System Description and Operation in SIR.

The front seat belts on sedans are equipped with an adjustable shoulder belt guide loop. The shoulder belt can be adjusted to one of the four positions by a release switch located at the center pillar. The release switch permits adjustment of the shoulder belt to the height of the occupant. The front passenger seat and the rear seat retractors are dual-mode type retractors with emergency locking and automatic features. The automatic locking feature is for use with a child seat. The front seat belt system includes the following components

1. Driver and the passenger seat belt retractors- The driver and passenger seat belt retractors are located and attached on the center pillar post in all coupes and sedans
2. The front seat center driver and passenger's buckle belts are located between the two front seats. These buckle belts are attached to the seat.
3. The driver seat belt system, includes a seat belt switch in the driver seat belt buckle which controls the fasten safety belt indicator and a tone alarm.

The rear seat belt system includes the following components

1. Rear seat belt retractors- The rear seat belt retractors are located under the rear deck trim panel. The rear seat belt retractors are attached to the rear deck body panel.
2. Rear seat center and outer seat buckle belts- The rear seat center and outer seat buckle belts are located in the center of the lower seat cushion. The rear seat center and outer seat buckle belts are attached to the rear floor pan.

Scheme 43

See also:
• SEAT BELT SYSTEM DESCRIPTION AND OPERATION
• SYMPTOMS - SEAT BELTS
• REPAIRS AND INSPECTIONS REQUIRED AFTER A COLLISION
• SEAT BELT INDICATOR CIRCUIT MALFUNCTION
• FASTENER TIGHTENING SPECIFICATIONS