Nissan Pathfinder: Dtc/circuit Diagnosis (B142x Collision Detection ... B2f60-55 Seat Belt Buckle Switch (driver Side))

• B142x Collision Detection
• B1400 Through B1420 Air Bag Diagnosis Sensor Unit
• B1500 Door Satellite Sensor
• B2c21-23 Seat Belt Buckle Switch (driver Side)
• B2f60-55 Seat Belt Buckle Switch (driver Side)

B142x Collision Detection Nissan Pathfinder SUV

DTC Description

DESCRIPTION

DTC DETECTION LOGIC

DTC No.	CONSULT screen items (Trouble diagnosis content)	DTC detecting condition
B1421	FRONTAL COLLISION	00	Diagnosis condition	Ignition switch ON.
			Signal (terminal)	—
			Threshold	—
			Diagnosis delay time	—
B1422	SIDE COLLISION	00	Diagnosis condition	Ignition switch ON.
			Signal (terminal)	—
			Threshold	—
			Diagnosis delay time	—
B1423	ROLLOVER DETECTION	00	Diagnosis condition	Ignition switch ON.
			Signal (terminal)	—
			Threshold	—
			Diagnosis delay time	—
B1425	REAR COLLISION	00	Diagnosis condition	Ignition switch ON.
			Signal (terminal)	—
			Threshold	—
			Diagnosis delay time	—

POSSIBLE CAUSE

[B1421-00]

• Malfunction of frontal-related parts

• Internal malfunction of air bag diagnosis sensor unit

[B1422-00]

• Malfunction of side-related parts

• Internal malfunction of air bag diagnosis sensor unit

[B1423-00]

• B1423–Malfunction of side-related parts

• Internal malfunction of air bag diagnosis sensor unit

[B1425-00]

• B1425–Malfunction of rear-related parts

• Internal malfunction of air bag diagnosis sensor unit

FAIL-SAFE

—

DTC CONFIRMATION PROCEDURE (With CONSULT)

INSPECTION START

Ignition switch ON.

>>

GO TO 2.

CHECK SELF-DIAG RESULT

CONSULT

Check for DTC.

Is the DTC detected?

YES>>

Refer to Diagnosis Procedure.

NO>>

Inspection End.

Diagnosis Procedure

Refer to For Frontal Collision or For Side and Rollover Collision.

B1400 Through B1420 Air Bag Diagnosis Sensor Unit Nissan Pathfinder 2025

DTC Description

DTC DETECTION LOGIC

DTC No.	CONSULT screen items (Trouble diagnosis content)	DTC detecting condition
B1400 through B1420	CONTROL UNIT [UNIT MALFUNC]	00	Diagnosis condition	Ignition switch ON.
			Signal (terminal)	—
			Threshold	—
			Diagnosis delay time	—

POSSIBLE CAUSE

Malfunction in air bag diagnosis sensor unit

FAIL-SAFE

—

DTC CONFIRMATION PROCEDURE (With CONSULT)

CHECK SELF-DIAG RESULT

CONSULT

1. Ignition switch ON.

2. Check for DTC.

Is the DTC detected?

YES>>

Refer to Diagnosis Procedure.

YES>>

GO TO 2.

NO>>

Inspection End.

ERASE SELF-DIAG RESULT

CONSULT

Erase the DTC.

Can the DTC be erased?

YES>>

Inspection End.

NO>>

Refer to Diagnosis Procedure.

DTC CONFIRMATION PROCEDURE (Without CONSULT)

CHECK SELF-DIAG RESULT

1. Ignition switch ON.

2. Check the air bag warning lamp status. Refer to Trouble Diagnosis without CONSULT.

NOTE:

SRS will not enter diagnosis mode if no malfunction is detected in user mode.

Is the DTC detected?

YES>>

Refer to Diagnosis Procedure.

NO>>

Inspection End.

Diagnosis Procedure

WARNING:

• Before servicing, ignition switch OFF, disconnect battery negative terminal, and wait at least 3 minutes or more. (To discharge backup capacitor.)

• Never use unspecified tester or other measuring device.

HARNESS CONNECTOR

Visually inspect all applicable harness connectors for the following:

• Visible damage to connector or terminal

• Loose terminal

• Poor connection

  NOTE:

  All harness connectors should be inspected from the air bag diagnosis sensor unit to the end component (including any in-line connectors).

Is the inspection result normal?

YES>>

GO TO 2.

NO>>

Perform one of the following repairs:

• Visible damage: Replace the harness.

• Loose terminal: Secure the terminal.

• Poor connection: Secure the connection.

CONFIRM DTC

CONSULT

1. Reconnect all harness connectors.

2. Ignition switch ON.

3. Check for DTC.

Is DTC still current?

YES>>

GO TO 3.

NO>>

Refer to Intermittent Incident.

WIRING HARNESS

Check the wiring harness for visible damage.

NOTE:

The entire wiring harness should be inspected from the air bag diagnosis sensor unit to the end component (including any in-line connectors).

Is the inspection result normal?

YES>>

GO TO 4.

NO>>

Replace the harness.

CONFIRM DTC

CONSULT

1. Reconnect all harness connectors.

2. Ignition switch ON.

3. Check for DTC.

Is DTC still current?

YES>>

GO TO 5.

NO>>

Refer to Intermittent Incident.

AIR BAG DIAGNOSIS SENSOR UNIT

CONSULT

1. Replace the air bag diagnosis sensor unit. Refer to Removal and Installation.

2. Ignition switch ON.

3. Check for DTC.

Is DTC still current?

YES>>

GO TO 6.

NO>>

Clear DTC. Inspection End.

RELATED HARNESS

Replace the related harness.

>>

Inspection End.

B1500 Door Satellite Sensor Nissan Pathfinder 2025

DTC Description

DTC DETECTION LOGIC

DTC No.	CONSULT screen items (Trouble diagnosis content)	DTC detecting condition
B1500	DOOR SATELLITE SENSOR [PERFRM ERR/INCRCT OPE]	92	Diagnosis condition	Ignition switch ON.
			Signal (terminal)	Front door satellite sensor
			Threshold	—
			Diagnosis delay time	—
	DOOR SATELLITE SENSOR [UPPER LIMIT ERR]	24	Diagnosis condition	Ignition switch ON.
			Signal (terminal)	Front door satellite sensor
			Threshold	—
			Diagnosis delay time	—
	DOOR SATELLITE SENSOR [LOWER LIMIT ERR]	23	Diagnosis condition	Ignition switch ON.
			Signal (terminal)	Front door satellite sensor
			Threshold	—
			Diagnosis delay time	—

POSSIBLE CAUSE

[PERFRM ERR/INCRCT OPE], [LOWER LIMIT ERR], [UPPER LIMIT ERR]

• Internal malfunction of front door satellite sensor

• Internal malfunction of air bag diagnosis sensor unit

FAIL-SAFE

—

DTC Confirmation Procedure

CHECK SELF-DIAG RESULT

CONSULT

1. Ignition switch ON.

2. Select “Self Diagnostic Result” mode of “AIR BAG”.

CONSULT

1. Ignition switch ON.

2. Check the air bag warning lamp status. Refer to Trouble Diagnosis without CONSULT.

NOTE:

SRS does not enter the diagnosis mode if no malfunction is detected in the user mode.

Is malfunctioning part detected?

YES>>

Refer to Diagnosis Procedure.

NO>>

To check malfunction symptom before repair: Refer to Intermittent Incident.

NO>>

Confirmation after repair: Inspection End.

Diagnosis Procedure

WARNING:

• Before servicing, place ignition switch to OFF, disconnect battery negative terminal, and wait at least 3 minutes or more. (To discharge backup capacitor.)

• Never use unspecified tester or other measuring device.

CHECK HARNESS CONNECTOR

Check the harness connector.

Is the inspection result normal?

YES>>

GO TO 2.

NO>>

Replace harness connector.

CHECK WIRING HARNESS

Check the wiring harness externals.

Is the inspection result normal?

YES>>

GO TO 3.

NO>>

Replace wiring harness.

REPLACE FRONT DOOR SATELLITE SENSOR LH AND RH

1. Replace front door satellite sensor LH and RH. Refer to Removal and Installation.

2. Perform DTC confirmation procedure. Refer to DTC Description.

Is DTC detected?

YES>>

GO TO 4.

NO>>

Inspection End.

REPLACE AIR BAG DIAGNOSIS SENSOR UNIT

1. Replace air bag diagnosis sensor unit. Refer to Removal and Installation.

2. Perform DTC confirmation procedure. Refer to DTC Description.

Is DTC detected?

YES>>

GO TO 1.

NO>>

Inspection End.

B2c21-23 Seat Belt Buckle Switch (driver Side) Nissan Pathfinder SUV

DTC Description

DTC DETECTION LOGIC

DTC No.	CONSULT screen items (Trouble diagnosis content)	DTC detecting condition
B2C21–23	Seat belt buckle switch (driver side) [Seat belt buckle switch (driver side)]	Diagnosis condition	Ignition switch ON
		Signal (terminal)	Seat belt buckle switch (front LH) signal (BCM connector terminal: 17)
		Threshold	When the ON/OFF change of seat belt buckle switch cannot be detected even once when all the following conditions are satisfied 10 times. Engine running Nissan Pathfinder Vehicle speed: 1.86 mph (3 km/h) or more
		Diagnosis delay time	—

POSSIBLE CAUSE

• Front seat belt buckle switch (LH)

• Harness or connectors (front seat belt buckle switch (LH) circuit is open or shorted)

FAIL-SAFE

Inhibit engine start/stop system

DTC CONFIRMATION PROCEDURE

CHECK SELF-DIAG RESULT

CONSULT

1. Start the engine.

2. Front seat belt LH is fastened.

3. Drive Nissan Pathfinder vehicle at a speed of 1.86 mph (3 km/h) or more

4. Ignition switch OFF.

5. Front seat belt LH is released.

6. Repeat steps from 1 to 5 (total 10 times).

7. Check “Self Diagnostic Result” mode of “BCM” .

Is DTC detected?

YES>>

Refer to DTC Diagnosis Procedure .

NO>>

To check malfunction symptom before repair: Refer to Intermittent Incident.

NO>>

Confirmation after repair: Inspection End.

Diagnosis Procedure

CHECK SEAT BELT BUCKLE SWITCH INPUT SIGNAL

1. Ignition switch OFF.

2. Check voltage between front seat belt buckle switch (LH) harness connector and ground.

   (+)		(–)	Condition		Voltage (Approx.)
   Front seat belt buckle switch (LH)
   Connector	Terminal
   B225	1	Ground	Front seat belt buckle switch (LH)	OFF (seat belt is released)	Battery Voltage
   				ON (seat belt is fastened)	0 V

Is the inspection result normal?

YES>>

GO TO 3.

NO>>

GO TO 2.

CHECK SEAT BELT BUCKLE SWITCH CIRCUIT

1. Disconnect front seat belt buckle switch (LH) connector and BCM connector.

2. Check continuity between front seat belt buckle switch (LH) harness connector and BCM harness connector.

   Front seat belt buckle switch (LH)		BCM		Continuity
   Connector	Terminal	Connector	Terminal
   B225	1	M18	17	Yes

3. Check continuity between BCM harness connector and ground.

   BCM		-	Continuity
   Connector	Terminal
   M18	17	Ground	No

Is the inspection result normal?

YES>>

Replace BCM. Refer to Removal and Installation .

NO>>

Repair or replace harness.

CHECK SEAT BELT BUCKLE SWITCH GROUND CIRCUIT

1. Disconnect front seat belt buckle switch (LH) connector.

2. Check continuity between front seat belt buckle switch (LH) harness connector and ground.

   Front seat belt buckle switch (LH)		-	Continuity
   Connector	Terminal
   B225	2	Ground	Yes

Is the inspection result normal?

YES>>

GO TO 4.

NO>>

Repair or replace harness.

CHECK SEAT BELT BUCKLE SWITCH (LH)

Check seat belt buckle switch (LH). Refer to Component Inspection .

Is the inspection result normal?

YES>>

Inspection End.

NO>>

Replace front seat belt buckle (LH). Refer to Removal and Installation .

Component Inspection

CHECK SEAT BELT BUCKLE SWITCH

1. Ignition switch OFF.

2. Disconnect front seat belt buckle switch LH connector.

3. Check continuity of front seat belt buckle switch LH terminals.

   Front seat belt buckle switch LH		Condition	Continuity
   Terminal
   1	2	When front seat belt LH is not fastened	Yes
   		When front seat belt LH is fastened	No

Is the inspection result normal?

YES>>

Inspection End.

NO>>

Replace front seat belt buckle LH. Refer to Removal and Installation .

B2f60-55 Seat Belt Buckle Switch (driver Side) Nissan Pathfinder R53

DTC Description

DTC DETECTION LOGIC

DTC No.	CONSULT screen items (Trouble diagnosis content)	DTC detecting condition
B2F60-55	Seat belt buckle switch (driver side) [Seat belt buckle switch (driver side)]	Diagnosis condition	Ignition switch ON
		Signal (terminal)	—
		Threshold	Configuration of the BCM is not completed
		Diagnosis delay time	1 second or less

POSSIBLE CAUSE

BCM is not configured

FAIL-SAFE

—

DTC CONFIRMATION PROCEDURE

CHECK SELF-DIAG RESULT

CONSULT

1. Ignition switch ON.

2. Check “Self Diagnostic Result” mode of “BCM” .

Is DTC detected?

YES>>

Refer to DTC Diagnosis Procedure.

NO>>

To check malfunction symptom before repair: Refer to Intermittent Incident.

NO>>

Confirmation after repair: Inspection End.

Diagnosis Procedure

BCM CONFIGURATION

Perform configuration. Refer to Work Procedure .

Is the DTC detected?

YES>>

GO TO 2.

NO>>

Inspection End.

REPLACE BCM

Replace BCM. Refer to Removal and Installation .

>>

Inspection End.