DESCRIPTION
- The air bag deploys if the air bag diagnosis sensor unit is activated while the ignition switch is in the ON or START position.
- The collision modes for which supplemental restraint systems are activated are different among the SRS systems. For example, the driver air bag module, front passenger air bag module and front seat belt pre-tensioners are activated in a frontal collision but not in a side collision.
| SRS configuration | Frontal collision | Left side collision | Right side collision |
|---|---|---|---|
| Driver air bag module | X | ||
| Front passenger air bag module | X | ||
| Front LH seat belt pre-tensioner | X | ||
| Front RH seat belt pre-tensioner | X | ||
| Front LH side air bag module | X | ||
| Front RH side air bag module | X | ||
| LH side curtain air bag module | X | ||
| RH side curtain air bag module | X |
SRS COLLISION MODES DESCRIPTION
Scheme 1
The occupant classification system (OCS) identifies different size occupants, out of position occupants, and detects if child seat is present in the front passenger seat. The OCS control unit (2) receives inputs from the occupant classification sensors (1) (located on the passenger seat track assembly). Depending on classification of the passenger, the OCS sends a signal to the air bag diagnosis sensor unit. The air bag diagnosis sensor unit uses this signal and the seat belt buckle switch RH signal to determine deployment or non deployment of the passenger front air bag in the event of a collision. Depending on the signals received, the air bag diagnosis sensor unit can disable the passenger front air bag completely. The OCS (weight sensors) must be set to zero point using CONSULT after servicing the OCS system.
Note. CONSULT can be used to confirm when "zero point reset" for OCS is complete. Always perform zero point reset after the removal and installation of the seat or when disconnecting the OCS control unit harness connector even if zero point reset has been completed in the past. If zero point reset is incomplete, the passenger air bag will be disabled and the passenger air bag off indicator will be ON. In case of customer concern, CONSULT can be used to confirm the passenger air bag status (readiness).
| Front Passenger Seat (Condition) | PASS AIR BAG OFF Indicator (Status) | Passenger Air Bag Status (Readiness) | CONSULT Display |
|---|---|---|---|
| Seat occupied | OFF | Active (enabled) | ON |
| Seat occupied (1) | ON | Deactivated (disabled) | OFF |
| Seat empty | OFF | Deactivated (disabled) | OFF |
| (1) Passenger does not meet Occupant Classification System specifications for passenger air bag activation. | |||
| (1) | Passenger does not meet Occupant Classification System specifications for passenger air bag activation. |
PASSENGER AIR BAG STATUS CONDITIONS
Scheme 2
Scheme 3
The seat belt warning lamp (1) will remind the driver if the driver or front passenger seat belt should be buckled. The system works in conjunction with the occupant classification system. Refer to " OCCUPANT CLASSIFICATION SYSTEM: SYSTEM DESCRIPTION ".
Scheme 4
| Driver seat status (Ignition switch ON) | Passenger seat status | Seat belt buckle switch LH status | Seat belt buckle switch RH status | Seat belt warning lamp |
|---|---|---|---|---|
| Seat occupied | Seat occupied | Buckled | Buckled | Off |
| Unbuckled | On | |||
| Seat unoccupied | Off | |||
| Unbuckled | On |
SEAT BELT WARNING SYSTEM OPERATION DESCRIPTION
| CAUTION | Never use electrical test equipment on any circuit related to the SRS unless instructed in this Service Information. SRS wiring harnesses can be identified by yellow and/or orange harnesses or harness connectors. Never repair, splice or modify the SRS wiring harness. If the harness is damaged, replace it with a new one. Keep ground portion clean. |
DIAGNOSIS FUNCTION
- The SRS self-diagnostic results can be read with air bag warning lamp and/or CONSULT.
- The user mode is exclusively prepared for the customer (driver). This mode warns the driver of a system malfunction through the operation of the air bag warning lamp.
- The diagnosis mode allows the technician to locate and inspect the malfunctioning part.
- The mode applications for the air bag warning lamp and CONSULT are as per the following items.
| X: Application, -: Not application | ||
|---|---|---|
| Diagnosis tool | User mode | Diagnosis mode |
| Air bag warning lamp | X | X |
| CONSULT | X | |
ADDITIONAL SERVICE WHEN REPLACING CONTROL UNIT: Description
Always perform zero point reset using CONSULT when removing and installing the passenger seat or servicing the occupant classification system. If zero point reset is not performed the OCS may not operate normally, which may increase the risk of serious injury in a collision.
ZERO POINT RESET: Description
Zero point reset is an initializing procedure for occupant detection sensor that must be performed when replacing or removing and installing passenger seat.
If zero point reset is not performed, the initialization is incomplete and Occupant Detection System does not operate normally.
Note. When zero point reset is performed once after removal and installation of passenger seat, CONSULT displays "complete". When reinstalling passenger seat after removal, the initial value for occupant detection sensor changes, and Occupant Detection System does not operate normally. Always perform zero point reset after performing the work as per the following. Reinstallation of passenger seat Installation of passenger seat that is zero point reset complete Installation of passenger seat that is zero point reset in complete
CAN (Controller Area Network) is a serial communication system for real time application. It is an on-vehicle multiplex communication system with high data communication speed and excellent error detection ability. Many electronic control units are equipped into vehicles, and each control unit shares information and links with other control units during operation. With CAN communication, control units are connected with two communication lines (CAN-H line, CAN-L line) allowing a high rate of information transmission with less wiring. Each control unit transmits and receives data but selectively reads required data only. Refer to " CAN COMMUNICATION SYSTEM: CAN COMMUNICATION SIGNAL CHART ".
Air bag diagnosis sensor performs self-tests on key ON. If CAN communication failure within control unit is detected, DTC is set.