SIR Disabling and Enabling
SIR component location affects how a vehicle should be serviced.
There are parts of the SIR system installed in various locations
around a vehicle. To find the location of the SIR components refer
to
SIR Identification Views .
There are several reasons for disabling the SIR system, such as
repairs to the SIR system or servicing a component near or attached
to an SIR component. There are several ways to disable the SIR
system depending on what type of service is being performed. The
following information covers the proper procedures for
disabling/enabling the SIR system.
Condition
|
Action
|
If the vehicle was involved in an accident with an air bag
deployment.
|
Disconnect the negative battery cable(s).
|
When performing SIR diagnostics.
|
Follow the appropriate SIR service manual diagnostic procedure(s)
*
|
When moving, removing or replacing an SIR component or a component
attached to an SIR component. (Anytime you remove fasteners.)
|
Disconnect the negative battery cable(s) *
|
If the vehicle is suspected of having shorted electrical
wires.
|
Disconnect the negative battery cable(s) *
|
When performing electrical diagnosis on components other than the
SIR system.
|
Remove the SIR/Airbag fuse(s) when indicated by the diagnostic
procedure to disable the SIR system
|
* DTCs will be lost when the negative battery cable is
disconnected.
|
|
|
SIR Service Precautions
|
Warning:
When performing service on or near the SIR
components or the SIR wiring, the SIR system must be disabled.
Failure to observe the correct procedure could cause deployment of
the SIR components. Serious injury can occur. Failure to observe
the correct procedure could also result in unnecessary SIR system
repairs. |
The inflatable restraint sensing and diagnostic module (SDM)
maintains a reserved energy supply. The reserved energy supply
provides deployment power for the air bags if the SDM loses battery
power during a collision. Deployment power is available for as much
as 1 minute after disconnecting the vehicle power. Waiting 1 minute
before working on the system after disabling the SIR system
prevents deployment of the air bags from the reserved energy
supply.
General Service Instructions
The following are general service instructions which must be
followed in order to properly repair the vehicle and return it to
its original integrity:
• |
Do not expose inflator modules
to temperatures above 65°C (149°F). |
• |
Verify the correct replacement
part number. Do not substitute a component from a different
vehicle. |
• |
Use only original GM
replacement parts available from your authorized GM dealer. Do not
use salvaged parts for repairs to the SIR system. |
Discard any of the following components if it has been dropped
from a height of 92 cm (3 feet) or greater:
• |
Inflatable restraint sensing
and diagnostic module (SDM) |
• |
Any Inflatable restraint air
bag module |
• |
Inflatable restraint steering
wheel module coil |
• |
Any Inflatable restraint
sensor |
• |
Inflatable restraint seat belt
pretensioners |
• |
Inflatable restraint passenger
presence detection module or sensor |
Disabling Procedure - Air Bag Fuse
1. |
Turn the steering wheel so
that the vehicles wheels are pointing straight ahead. |
2. |
Place the ignition in the OFF
position. |
|
Note: The SDM may
have more than one fused power input. To ensure there is no
unwanted SIR deployment, personal injury, or unnecessary SIR system
repairs, remove all fuses supplying power to the SDM. With all SDM
fuses removed and the ignition switch in the ON position, the AIR
BAG warning indicator illuminates. This is normal operation, and
does not indicate a SIR system malfunction.
|
4. |
Wait 1 minute before working
on the system. |
Enabling Procedure - Air Bag Fuse
1. |
Place the ignition in the OFF
position. |
3. |
Turn the ignition switch to
the ON position. The AIR BAG indicator will flash then turn
OFF. |
Disabling Procedure - Negative Battery Cable
1. |
Turn the steering wheel so
that the vehicles wheels are pointing straight ahead. |
2. |
Place the ignition in the OFF
position. |
4. |
Wait 1 minute before working
on system. |
Enabling Procedure - Negative Battery Cable
1. |
Place the ignition in the OFF
position. |
3. |
Turn the ignition switch to
the ON position. The AIR BAG indicator will flash then turn
OFF. |
|