Suzuki XL7 2007 Service Manual page 2017

Inflatable Restraint Roof Rail Modules
The roof rail modules are located under the headliner
extending from the front windshield pillar to the rear
window pillar. The roof rail modules contain a housing,
inflatable air bag, initiating device, and a canister of gas
generating material. The initiator is part of the roof rail
module deployment loop. When a side impact of
sufficient force occurs the SIS detects the impact and
sends a signal to the sensing and diagnostic module
(SDM). The SDM compares the signal received from the
SIS to a value stored in memory. When the generated
signal exceeds the stored value, the SDM will cause
current to flow through the side deployment loop
deploying the roof rail air bags. The SDM, roof rail
modules, and the connecting wires make up the side
deployment loops. The SDM continuously monitors the
deployment loops for malfunctions and turns the AIR
BAG indicator ON if a fault is present.
Each roof rail module is equipped with a shorting bar
located on the connector of the module. The shorting bar
shorts the roof rail module deployment loop circuitry to
prevent unwanted deployment of the air bag when
servicing the inflator module.
SIR Schematic Icons
Icon
Schematic and Routing Diagram
WARNING
!
When performing service on or near the SIR components or the SIR
wiring, the SIR system must be disabled. Refer to SIR Disabling and
Enabling. Failure to observe the correct procedure could cause
deployment of the SIR components, personal injury, or unnecessary
SIR system repairs.
NOTE
• In order to prevent accidental deployment, the shorting bars close in
order to short the connectors when the connectors are separated.
• Twisted-pair wires provide an effective shield that helps protect
sensitive electronic components from electrical interference. If the
wires were covered with shielding, install new shielding.
In order to prevent electrical interference from degrading the
performance of the connected components, you must maintain the
proper specification when making any repairs to the twisted-pair
wires shown:
– The wires must be twisted a minimum of 9 turns per 31 cm (12 in)
as measured anywhere along the length of the wires
– The outside diameter of the twisted wires must not exceed 6.0 mm
(0.25 in)
Inflatable Restraint Side Impact Sensor (SIS)
The side impact sensor (SIS) contains a sensing device
which monitors vehicle acceleration and velocity
changes to detect side collisions that are severe enough
to warrant air bag deployment. The SIS is not part of the
deployment loop, but instead provides an input to the
sensing and diagnostic module (SDM). The SDM
contains a microprocessor that performs calculations
using the measured accelerations and compares these
calculations to a value stored in memory. When the
generated calculations exceed the stored value, the
SDM will cause current to flow through the deployment
loops deploying the roof rail module air bags.
Inflatable Restraint Wiring Harness
The inflatable restraint wiring harnesses connect the
inflators modules, sensing and diagnostic module
(SDM), deployment loops, and class 2 serial data
together using weather pack connectors. SIR system
connectors are yellow in color for easy identification.
When repairing the SIR wiring harnesses follow the
proper testing and wiring repair procedures listed in this
manual.
Icon Definition
Air Bag System: 8B-5