SECTION 8B
SUPPLEMENTAL INFLATABLE RESTRAINTS (SIR)
Caution : Disconnect the negative battery cable before removing or installing any electrical unit or when a tool or equipment could easily come in contact with exposed electrical terminals. Disconnecting this cable will help prevent personal injury and damage to the vehicle. The ignition mujst be also be in LOCK unless otherwise noted
SPECIFICATIONS
General Specifications
Application | Description |
Airbag System Deployment Time | <20ms |
Detection Time | <5ms |
Operating Temperature | -40°C~+85°C |
Storage Temperature | -40°C~+90°C |
Normal Operating Voltage Range | 10~16.5V |
Deployment Current | 1.2~1.9A for 2ms |
Energy Reservation (Only Frontal Deployment Loops) | 75ms after battery disconnection |
Inflator Ignition Energy | 4.3mj |
Squib Resistance | 2 +/- 0.3Ω |
Airbag Warning Lamp ON Time(When Ignition ON) | 7sec |
Fastener Tightening Specifications
Application | N·m | Lb-Ft | Lb-In |
Clock Spring Retaining Screws | 1.25 | - | 11 |
Passenger Airbag Module Mounting Bolts | 10 | 7 | - |
Passenger Airbag Module Mounting Nuts | 10 | 7 | - |
Sensing and Diagnostic Module(SDM) Mounting Bolts | 10 | 7 | - |
Roof Rail (Head Curtain) Airbag Module Mounting Bolts | 10 | 7 | - |
Side Airbag Sensor Mounting Bolt | 10 | 7 | - |
SPECIAL TOOLS
SPECIAL TOOLS TABLE
SCHEMATIC AND ROUTING DIAGRAMS
Supplemental Inflatable Restraints(SIR) Electronical Schematic
SIR Component Locator
- Driver Airbag Module
- Passenger Airbag Module
- Sensing And Diagnostic Module(SDM)
- Side Impact Sensor
- Clock Spring
- Side Airbag Module
- Seat Belt Buckle Pretensioner
- Roof Rail (Head Curtain) Airbag Module
- Passenger Seat Belt Reminder Sensor
DIAGNOSIS
Diagnostic Trouble Code (DTC)
When the sensing and diagnostic module (SDM) detects any problem it illuminates the airbag warning indicator and stores the diagnostic trouble codes (DTCs).
The supplemental inflatable restraints (SIR) diagnostic system check must be always the starting point for any SIR diagnosis. The diagnostic system check reveals diagnostic trouble codes (DTCs) through the use of scan tool. It also checks for proper airbag warning lamp operation.
The two types of DTCs that may be recorded are as follows :
- Active DTCs represent malfunction being detected during the current ignition cycle. Active DTCs are stored in random access memory (RAM).
- Historic DTCs represent malfunctions detected sincethe last time the historic memory was cleared. Historic DTCs are stored in the electrically erasable programmable read-only memory (EEPROM).
Diagnostic Trouble Code Table
DTC & Description | DTC symptom | Warning Lamp |
B0012 Left Front / Driver Frontal Deployment Loop | Resistance Too High | Yes |
Open Circuit | . |
Resistance Too Low | . |
Short to Ground | . |
Short to Battery | . |
B0014 Left Front / Driver Side Deployment Loop | Resistance Too High | Yes |
Open Circuit | . |
Resistance Too Low | . |
Short to Ground | . |
Short to Battery | . |
B0015 Left Front / Driver Pretensioner Deployment Loop | Resistance Too High | Yes |
Open Circuit | . |
Resistance Too Low | . |
Short to Ground | . |
Short to Battery | . |
B0016 Left Front / Driver Roof Rail / Head Curtain Deployment Loop | Resistance Too High | Yes |
Open Circuit | . |
Resistance Too Low | . |
Short to Ground | . |
Short to Battery | . |
B0019 Right Front / Passenger Frontal Deployment Loop | Resistance Too High | Yes |
Open Circuit | . |
Resistance Too Low | . |
Short to Ground | . |
Short to Battery | . |
B0021 Right Front / Passenger Side Deployment Loop | Resistance Too High | Yes |
Open Circuit | . |
Resistance Too Low | . |
Short to Ground | . |
Short to Battery | . |
B0022 Right Front / Passenger Pretensioner Deployment Loop | Resistance Too High | Yes |
Open Circuit | . |
Resistance Too Low | . |
Short to Ground | . |
Short to Battery | . |
B0023 Right Front / Passenger Roof Rail / Head Curtain Deployment Loop | Resistance Too High | Yes |
Open Circuit | . |
Resistance Too Low | . |
Short to Ground | . |
Short to Battery | . |
B0052 Deployment Commanded | - | Yes |
B0053 Deployment Commanded with Loop DTCs Present | - | Yes |
B0055 Side Airbag Deployment Commanded | - | Yes |
B0085 Left Front / Driver Side Impact Sensor (SIS) | Internal electronic failure/discard | Yes |
Incorrect component installed | . |
Short to Ground | . |
Short to Ground or Open | . |
Short to Battery | . |
Invalid serial data received | . |
Erratic | . |
B0086 Right Front / Passenger Side Impact Sensor (SIS) | Internal electronic failure/discard | Yes |
Incorrect component installed | . |
Short to Ground | . |
Short to Ground or Open | . |
Short to Battery | . |
Invalid serial data received | . |
Erratic | . |
B1000 Electronic Control Unit (ECU) Performance | - | Yes |
B1001 Incorrect Vehicle (SDM Failed correct vehicle check) | - | Yes |
B1019 SDM System Configuration Error | - | Yes |
B1370 Run / Crank Circuit (Device IGN1) | Short to Ground or Open | No |
U0073 Conrol Module Communication Bus Off | - | No |
U0140 Lost Communication With BCM | - | No |
U0155 Lost Communication With IPC | - | No |
Scan Tool Diagnostics
A scan tool can read serial data from terminal 1 of the data link connector(DLC) by using low speed GMLAN. The scan tool is used to read diagnostic trouble codes(DTCs), and to clear some DTCs after a repair is completed.
To use the scan tool, turn the ignition OFF, connect the scan tool to the DLC, and turn the ignition switch to ON.
Follow the instructions in the scan tool manual. The SDM sends serial data from terminal 2 of the SDM to terminal 1 of the DLC with the other control modules.
SIR Diagnostic System Check
Notice : If the vehicle interior has been exposed to extensive water intrusion such as water leaks, driving through high water, flooding, or other causes, the sensing and diagnostic module(SDM) and SDM connector may need to be replaced. With ignition OFF, inspect the area around the SDM, including the carpet. If any significant soaking or evidence of previous soaking is detected, the water must be removed, water damage repaired, and the SDM and the SDM connector must be replaced. Before attempting any of these repairs, the supplemental inflatable restraints(SIR) must be disabled. Refer to "Disabling the SIR" and "Sensing and Diagnostic Module(SDM)" in this section for instructions on how to disable the SIR and replace the SDM.
The SIR Diagnostic System Check must always be the starting point for any SIR diagnosis. The Diagnostic System Check reveals diagnostic trouble codes(DTCs) through the use of scan tool. The diagnostic procedures used in this section are designed to find any repair SIR conditions. To get the best results, it is important to use the diagnostic charts and follow the sequence listed below.
- Perform the SIR Diagnostic System Check, which reveal diagnostic trouble codes(DTCs) through the use of scan tool.. It also checks for proper airbag indicator operation.
- Refer to the proper diagnostic chart as directed by SIR Diagnostic System Check. Bypassing these procedures may result in extended diagnostic time, incorrect diagnosis, and incorrect parts replacement.
- Repeat the SIR Diagnostic System Check after any repair or diagnostic procedures have been performed to ensure that the repair has been made correctly and that no other malfunction exists.
Circiut Description
The SDM receive the voltage from the battery as main power source at the terminal 31 of SDM. Additionally when the ignition voltage is supplied from I/P fuse block into the terminal 32 of SDM as backup power source. The SDM responds by flashing the airbag indicator seven times and then turning it off while the SDM performs tests on the SIR.
Diagnostic Aids
The order in which DTCs are diagnosed is very important. Failure to diagnose the DTCs in the order specified may result in extended diagnostic time, incorrect diagnosis, and incorrect parts replacement.
SIR Diagnostic System Check
Caution : The sensing and the diagnosis module (SDM) can maintain surfficient voltage to deploy the airbags and pretensioners for 1 minute after the ignition is OFF and the fuse has been removed. If the airbags and pretensioners are not disconnected, do not begin service until one minute has been passed after disconnecting power to the SDM. Otherwise, injury could result.
Caution : During service procedure, be very careful when handling the SDM. Never strike or jar the SDM. Never power the supplemental inflatable restraints(SIR) when the SDM is not rigidly attached to the vehicle. All SDM mounting bolts must be carefully tightened , and the arrow on the SDM must be point toward the front of the vehicle to ensure proper operation of the SIR. The SDM could be activated if it is powered when it is not rigidly attached to the vehicle, resulting in unexpected deployment and possible injury.
| Step | Action | Value(s) | Yes | No |
| 1 | - Turn the ignition switch ON.
- Observe the airbag indicator as the ignition is being turned ON. Does the indicator flash seven times?
| - | System OK | Go to Step 2 |
| 2 | - Turn the ignition to LOCK and remove the key.
- Connect the scan tool to the data link connector(DLC).
- Are any SIR's DTCs displayed on the scan tool?
| - | Go to the DTC check procedure | Go to Step 3 |
| 3 | Check the fuse Ef2 in the engine fuse block. Is the fuse Ef2 blown? | - | Replace the fuse Ef2 | Go to Step 4 |
| 4 | Check the fuse F5 in the I/P fuse block. Is the fuse F5 blown? | - | Replace the fuse F5 | Go to Step 5 |
| 5 | - Disconnect the connector X203.
- Check the wiring open or short between the terminal 14 of I/P fuse block and the terminal 6 of the connector X203.
Is the wiring open or shorted? Then, repair the wiring. | - | - | Go to Step 6 |
| 6 | - Disconnect the connector from the SDM.
- Disconnect the connector from the SDM.
- Check the wiring open or short between the terminal 31 of the SDM connector and the terminal 6 of the connector X203.
- Check the wiring open or short between the terminal 31 of the SDM connector and the terminal 6 of the connector X203.
Is the wiring open or shorted? Then, replace the airbag wiring. | - | - | Go to Step 7 |
| 7 | - Check the wiring open or short between the terminal 1 of the DLC and the ground.
- Is the wiring open or shorted? Then, repair the wiring.
| - | - | Go to Step 8 |
| 8 | - Confirm the ignition switch ON.
- Check the power supply for the scan tool.
Is the scan tool receiving the correct voltage? | 9 - 16V | Go to Step 10 | Go to Step 9 |
| 9 | Repair the power supply for the scan tool. | - | - | - |
| 10 | Check the wiring open or short between the terminal 8 of the SDM connector and the terminal 1 of the data link connector (DLC). Is the wiring open or shorted? Then repair the wiring. | - | - | Replace the SDM. |
Sensing and Diagnostic Module (SDM) Integrity Check
The following diagnostic chart must be used when all circuitry outside the sensing and diagnostic module (SDM) has been found to operate properly, as indicated by following the appropriate diagnostic trouble code(DTC) chart. The chart verifies the need for SDM replacement.
Circuit Description
When the SDM recognizes battery voltage greater than 9 volts at terminal 31 of the SDM, the airbag indicator flashes seven times to verify operation. At this time the SDM performs turn-on tests followed by resistance measurement tests and continuous monitoring tests.
When malfunction is detected, the SDM sets current DTC and illuminates the airbag indicator.
When the malfuncation is no longer detected and/or the ignition switch is cycled, the SDM will clear current DTCs and move them to a history file, except for the DTCs B0052, B0053, B0055, B1000, B1001, B1019. These DTCs will not be cleared by scan tool because these codes require replacement of SDM. The SDM must be replaced only after the malfunction that set the DTC has been repaired.
Sensing and Diagnostic Module (SDM) Integrity Check
Caution : The sensing and diagnostic module (SDM) can maimtain sufficient voltage to deploy the airbags and pretensioners for 1 minute after the ignition is OFF and the fuse has been removed. If the airbags and pretensioners are not disconnected, do not begin service until one minute has passed after disconnecting the power to the SDM. Otherwise, injury could result.
Caution : During service procedure, be very careful when handling the SDM. Never strike or jar the SDM. Never power the supplemental inflatable restraints(SIR) when the SDM is not rigidlyattached to the vehile. All SDM mounting bolts must be carefully tightened , and the arrow on the SDM must be point toward the front of the vehicle to ensure proper operation of the SIR. The SDM could be activated if it is powered when it is not rigidly attached to the vehicle, resulting in unexpected deployment and possible injury.
| Step | Action | Value(s) | Yes | No |
| 1 | - Turn the ignition to LOCK and remove the key
- Connect all SIR components and ensure that all the components are properly mounted.
- Ensure that the ignition switch has been OFF for at least 30 seconds.
- Observe the airbag indicator as the ignition is turned ON. Does the indicator lamp flashes seven times ?
| - | | Go to Step 2 |
| 2 | - Turn the ignition to LOCK and remove the key.
- Connect the scan tool to DLC.
- Turn the ignition to ON.
- Request SIR DTC display with the scan tool. Is the same DTC displayed that was previous occurred when the SIR Diagnostic System Check was previously performed?
| - | Go to Step 3. | Go to the table for the DTC indicated. |
| 3 | - Clear SIR DTCs.
- Turn the ignition OFF for at least 30 seconds.
- Observe the airbag indicator as the ignition is turned ON. Does the indicator lamp flashes seven times ?
| - | System OK | Go to Step4 |
| 4 | - Turn the ignition to LOCK and remove the key.
- Disconnect the SDM connector.
- Replace the SDM.
- Connect the SDM connector and ensure that all components are properly mounted. Is the repair complete?
| - | | - |
Hot In Run and Start
