Nissan Sentra B18 (2020-2025) Service Manual: Srs Air Bag Control System

Component Parts Location

Component Parts Location

A.	RH front passenger seat (view with seat removed from Nissan Sentra vehicle)	B.	Driver’s door area (view with door finisher removed)	C.	Driver’s side B-pillar (view with component removed from Nissan Sentra vehicle)
D.	Driver’s side headliner area (view with headliner removed)	E.	Driver’s side rear seat area (view with LH luggage side lower finisher removed)	F.	Driver’s side rear seat area (view with component removed from Nissan Sentra vehicle)

No.	Component	Function
1.	Rear seat belt buckle switch RH & CTR	Transmits the rear seat belt buckle switch RH & CTR signal to the air bag diagnosis sensor unit.
2.	Front RH side air bag module (LH similar)	Refer to Front Side Air Bag Module.
3.	Front seat belt buckle switch RH	Transmits the front seat belt buckle switch RH signal to the air bag diagnosis sensor unit.
4.	Front passenger air bag module	Refer to Front Passenger Air Bag Module.
5.	Right knee air bag module	Refer to Knee Air Bag Module.
6.	Crash zone sensor	Refer to Crash Zone Sensor.
7.	Left knee air bag module	Refer to Knee Air Bag Module.
8.	Air bag diagnosis sensor unit	Refer to Air Bag Diagnosis Sensor Unit.
9.	Driver air bag module	Refer to Driver Air Bag Module.
10.	Front seat belt buckle switch LH	The front seat belt buckle switch LH provides the front seat belt buckle switch LH signal to the air bag diagnosis sensor unit and the combination meter by BCM via CAN communication line.
11.	Rear seat belt buckle switch LH	Transmits the rear seat belt buckle switch LH signal to the air bag diagnosis sensor unit.
12.	Rear LH side air bag module (RH similar)	Refer to Rear Side Air Bag Module.
13.	Occupant classification system control unit	Refer to System Description.
14.	Occupant classification system sensors	Refer to System Description.
15.	Front door satellite sensor LH (RH similar)	Refer to Front Door Satellite Sensor.
16.	Front LH seat belt pre-tensioner (lap belt) (RH similar)	Refer to Front Seat Belt Pre-tensioner.
17.	Front LH seat belt pre-tensioner (shoulder belt) (RH similar)	Refer to Front Seat Belt Pre-tensioner.
18.	LH side curtain air bag module (RH similar)	Refer to Side Curtain Air Bag Module.
19.	Rear side air bag satellite sensor LH (RH similar)	Refer to Rear Side Air Bag Satellite Sensor.
20.	Rear LH seat belt pre-tensioner (RH similar)	Refer to Rear Seat Belt Pre-tensioner.

Driver Air Bag Module

Driver Air Bag Module

The driver air bag module is dual stage and located in the steering wheel assembly. It operates with the SRS system in a frontal collision exceeding a specified level.

Front Passenger Air Bag Module

Front Passenger Air Bag Module

The front passenger air bag module is dual stage and is located behind the instrument panel assembly. It operates with the SRS system in a frontal collision exceeding a specified level. Refer to System Description for more information.

Knee Air Bag Module

Knee Air Bag Module

The knee air bag modules are single stage. The left knee air bag module is located in the instrument panel assembly below the steering wheel. The right knee air bag module is located in the instrument panel below the glove box. They operate with the SRS system in a frontal collision exceeding a specified level.

Left Knee Air Bag Module Right Knee Air Bag Module

Front Side Air Bag Module

Front Side Air Bag Module

Front side air bag modules are built into the front seat back assemblies. Vehicles with side air bags are equipped with labels as shown.

Side Curtain Air Bag Module

Side Curtain Air Bag Module

Side curtain air bag modules are located above the vehicle headliner.

Vehicles with side curtain air bags are equipped with labels on the pillar upper finishers.

Rear Side Air Bag Module

Rear Side Air Bag Module

Rear side air bag modules are built into the rear seat back assemblies. Vehicles with side air bags are equipped with labels.

Front Seat Belt Pre-Tensioner

Front Seat Belt Pre-tensioner

The seat belt pre-tensioner system with load limiter is installed for both the driver's seat and the front passenger's seat. It operates simultaneously with the SRS air bag system in the event of a frontal collision with an impact exceeding a specified level.

When the frontal collision with an impact exceeding a specified level occurs, seat belt slack resulting from clothing or other factors is immediately taken up by the shoulder belt pre-tensioner (1) as well as the lap belt pre-tensioner (2). Nissan Sentra Vehicle passengers are securely restrained.

When passengers in a vehicle are thrown forward in a collision and the restraining force of the seat belt exceeds a specified level, the load limiter permits the specified extension of the seat belt by the twisting of the ELR shaft, and a relaxation of the chest-area seat belt web tension while maintaining force.

Air Bag Diagnosis Sensor Unit

Air Bag Diagnosis Sensor Unit

The air bag diagnosis sensor unit is located under the center console assembly. The air bag diagnosis sensor unit receives signals from multiple SRS sensors and controls the deployment of the air bags. The deployment of the air bags depends on the type and severity of the collision. The air bag diagnosis sensor unit has self-diagnosis capability through the use of the CONSULT as well as flash codes displayed by the air bag warning lamp.

Crash Zone Sensor

Crash Zone Sensor

The crash zone sensor is located in front of the radiator. The crash zone sensor sends signals to the air bag diagnosis sensor unit during a frontal collision. This sensor may be identified by a yellow connector.

Rear Seat Belt Pre-Tensioner

Rear Seat Belt Pre-tensioner

The rear seat belt pre-tensioner system is installed for both the left rear and right rear seats. It operates simultaneously with the SRS sir bag system in the event of frontal collision with an impact exceeding a specified level.

Rear Side Air Bag Satellite Sensor

Rear Side Air Bag Satellite Sensor

The rear side air bag satellite sensors are located behind the rear pillar lower finisher LH and RH. The rear side air bag satellite sensors send signals to the air bag diagnosis sensor unit during a side collision. These sensors may be identified by yellow connectors.

Front Door Satellite Sensor

Front Door Satellite Sensor

The front door satellite sensors are located in the driver and passenger doors. The sensors detect sudden pressure changes inside the door cavity and then send signals to the air bag diagnosis sensor unit during a side collision. These sensors may be identified by yellow connectors.