Nissan Sentra Service Manual: System
SRS air bag system
SRS AIR BAG SYSTEM : System Diagram
SRS AIR BAG SYSTEM : System 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 Collision Modes
Occupant classification system
OCCUPANT CLASSIFICATION SYSTEM : System Diagram
OCCUPANT CLASSIFICATION SYSTEM : System Description
The occupant classification system (OCS) identifies different size occupants, out of position occupants, and detects if a child seat is present in the front passenger seat. The OCS control unit (2) receives inputs from the occupant classification sensors (1) (located inside the passenger seat cushion 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 (passenger seat) 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).
Passenger Air Bag Status Conditions
NOTE:
Passenger does not meet Occupant Classification System specifications for passenger air bag activation.
Seat belt warning lamp system
SEAT BELT WARNING LAMP SYSTEM : System Diagram
SEAT BELT WARNING LAMP SYSTEM : System Description
The seat belt warning lamp (1) will remind the driver if the driver or front passenger (US/CAN models) seat belt should be buckled. The system works in conjunction with the occupant classification system.
Refer to SRC-12, "OCCUPANT CLASSIFICATION SYSTEM : System Description".
Seat Belt Warning System Operation
Component parts
Component Parts Location
Driver air bag module
Front passenger air bag off indicator
Front passenger air bag module
Front LH side air bag module
(RH similar)
LH side curtain air bag ...
Diagnosis system (AIR BAG)
Description
CAUTION:
Never use electrical test equipment on any circuit related to the
SRS unless instructed in this Service
Manual. SRS wiring harnesses can be identified by yellow and/or o ...
Other materials:
P0137 HO2S2
DTC Logic
DTC DETECTION LOGIC
The heated oxygen sensor 2 has a much longer switching time
between rich and lean than the air fuel ratio (A/F) sensor 1. The oxygen
storage capacity of the three way catalyst (manifold) causes the
longer switching time. To judge the malfunctions of heated oxygen
...
P050A, P050B, P050E Cold start control
Description
ECM controls ignition timing and engine idle speed when engine is started
with pre-warming up condition.
This control promotes the activation of three way catalyst by heating the
catalyst and reduces emissions.
DTC Logic
DTC DETECTION LOGIC
NOTE:
If DTC P050A, P050B or P050E ...
Ecm branch line circuit
Diagnosis procedure
1.Check connector
Turn the ignition switch off.
Disconnect the battery cable from the negative terminal.
Check the terminals and connectors of the ecm for damage, bend and loose
connection (unit side and
connector side).
Is the inspection result normal?
Yes > ...
