Grand Prix V6-191 3.1L (1989)
Seat Belt: All Technical Service Bulletins
Automatic Safety Belts - Manual Update
Bulletin Number:
91-8-10
Reference Number:
938146R
Publish Date:
3/91
Subject:
SERVICE MANUAL UPDATE - SECTION 8A-146 AUTOMATIC SAFETY BELTS (CIRCUIT OPERATION REVISION)
Models Affected;
1988-91 GRAND PRIX MODELS
Section 8A-146 Circuit Operation for the Automatic Safety Belts cell has been revised. Replace the existing Circuit Operation in the 1988, 1989, 1990
and 1991 Grand Prix Service Manuals with the Circuit operation below:
Circuit Operation
The purpose of the Passive Restraint Control Module is to allow the car doors to be opened without restriction by the safety belts. Without this feature,
the retractor lock pendulums would lock the belts as they are pulled out of the retractors, when a front door is opened for entry or for exit. This would
make it difficult to open the door. To overcome this difficulty, the safety belt locking mechanism is controlled by the Passive Restraint Control Module
which controls the operation of the safety belt retractor release solenoids.
The Passive Restraint Control Module receives power from the Belt Fuse. When a door handle switch is operated or a door is open, the associated Door
Latch Switch will close. The Module will close its output switch and energize all the Safety Belt Retractor Release Solenoids for both doors. The door
may then be opened without interference from the Safety Belts. The module will also turn on the key cylinder light to illuminate the left hand front door
lock cylinder. When the door is closed the Latch Switch opens again and the solenoids are de-energized after about three seconds. The belts are now
ready to protect the wearer and the key cylinder light will go out. To ensure that the solenoids are released, a vehicle speed signal is also supplied to the
Module. The Module will release the solenoids any time the car is moving, even if a Latch Switch is closed. If a Latch Switch fails to open and the
speed signal causes the solenoids to release, the solenoids cannot be energized again until the switch opens to reset the module.
Note:
A shorted latch switch will keep the Module from resetting, so both Safety Belts will interfere with door opening. An open Latch
Switch will still allow the system to operate properly when the other door is used.
