Nissan Leaf. Manual - part 1125

B142A IGN VOLTAGE

SRC-101

< DTC/CIRCUIT DIAGNOSIS >

C

D

E

F

G

I

J

K

L

M

A

B

SRC

N

O

P

B142A IGN VOLTAGE

Description

INFOID:0000000010877022

DTC B142A IGNITION VOLTAGE

Ignition voltage is supplied to the air bag diagnosis sensor unit when the ignition is in the ON position. The air

bag diagnosis sensor unit will monitor for low or high ignition voltage.

PART LOCATION

Refer to 

SRC-6, "Component Parts Location"

.

DTC Description

INFOID:0000000010877023

DTC DETECTION LOGIC

POSSIBLE CAUSE

[B142A–16]

• Malfunction of battery voltage (low voltage)

• Connection malfunction of harness or connector

• Internal malfunction of air bag diagnosis sensor unit

[B142A–17]

• Malfunction of battery voltage (high voltage)

• Connection malfunction of harness or connector

• Internal malfunction of air bag diagnosis sensor unit

FAIL-SAFE

—

DTC CONFIRMATION PROCEDURE (With CONSULT)

1.

CHECK SELF-DIAG RESULT

1. Turn ignition switch ON.

2. Check for DTC using CONSULT.
Is the DTC detected?

YES (Current DTC)>>Refer to 

SRC-102, "Diagnosis Procedure"

.

YES (Past DTC)>>GO TO 2.

NO

>> Inspection End.

2.

ERASE SELF-DIAG RESULT

Erase the DTC using CONSULT.
Can the DTC be erased?

YES

>> Inspection End.

NO

>> Refer to 

SRC-102, "Diagnosis Procedure"

.

DTC CONFIRMATION PROCEDURE (Without CONSULT)

1.

CHECK SELF-DIAG RESULT

1. Turn ignition switch ON.

2. Check the air bag warning lamp status. Refer to 

SRC-11, "On Board Diagnosis Function"

.

NOTE:

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

DTC

CONSULT screen items

(Trouble diagnosis content)

DTC detecting condition

B142A–16

IGNITION VOLTAGE
(Ignition voltage low)

[VB-LOW]

Power supply malfunction (low voltage) of air bag diagnosis sensor unit

B142A–17

IGNITION VOLTAGE
(Ignition voltage high)

[VB-HIGH]

Power supply malfunction (high voltage) of air bag diagnosis sensor unit

SRC-102

< DTC/CIRCUIT DIAGNOSIS >

B142A IGN VOLTAGE

Is the DTC detected?

YES

>> Refer to 

SRC-102, "Diagnosis Procedure"

.

NO

>> Inspection End.

Diagnosis Procedure

INFOID:0000000010877024

1.

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.

2.

CONFIRM DTC

1. Reconnect all harness connectors.

2. Turn ignition switch ON.

3. Check for DTC using CONSULT.
Is DTC still current?

YES

>> GO TO 3.

NO

>> Refer to 

GI-53, "Intermittent Incident"

.

3.

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.

4.

CONFIRM DTC

1. Reconnect all harness connectors.

2. Turn ignition switch ON.

3. Check for DTC using CONSULT.
Is DTC still current?

YES

>> GO TO 5.

NO

>> Refer to 

GI-53, "Intermittent Incident"

.

5.

AIR BAG DIAGNOSIS SENSOR UNIT

1. Replace the air bag diagnosis sensor unit. Refer to 

SR-38, "Removal and Installation"

.

2. Turn ignition switch ON.

3. Check for DTC using CONSULT.
Is DTC still current?

YES

>> GO TO 6.

NO

>> Clear DTC. Inspection End.

6.

RELATED HARNESS

Replace the related harness.

>> END

B142X COLLISION DETECTION

SRC-103

< DTC/CIRCUIT DIAGNOSIS >

C

D

E

F

G

I

J

K

L

M

A

B

SRC

N

O

P

B142X COLLISION DETECTION

Description

INFOID:0000000010877025

DTC B1421 and B1422 COLLISION DETECTION

The air bag diagnosis sensor unit will set this DTC if it has detected a collision or rollover which has resulted in

a deployment of one or more air bags or pre-tensioners. If this DTC is detected after a SRS repair, the air bag

diagnosis sensor unit has not yet been replaced. This DTC can not be erased.

PART LOCATION

Refer to 

SRC-6, "Component Parts Location"

.

DTC Description

INFOID:0000000010877026

DTC DETECTION LOGIC 

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

FAIL-SAFE

—

DTC CONFIRMATION PROCEDURE (With CONSULT)

1.

INSPECTION START

Turn ignition switch ON.

>> GO TO 2.

2.

CHECK SELF-DIAG RESULT

Check for the DTC on CONSULT.
Is the DTC detected?

YES

>> Refer to 

SRC-103, "Diagnosis Procedure"

.

NO

>> Inspection End.

Diagnosis Procedure

INFOID:0000000010877027

Refer to 

SR-13, "For Frontal Collision"

 or 

SR-15, "For Side and Rollover Collision"

.

DTC

CONSULT screen items

DTC detecting condition

B1421–00

FRONTAL COLLISION DETECTION

Frontal collision detected. Driver and/or front passenger air bag modules are de-
ployed.

B1422–00

SIDE COLLISION DETECTION

Side collision detected. Curtain air bag module and seat belt pre-tensioner are 
deployed.

SRC-104

< DTC/CIRCUIT DIAGNOSIS >

B14XX AIR BAG DIAGNOSIS SENSOR UNIT

B14XX AIR BAG DIAGNOSIS SENSOR UNIT

Description

INFOID:0000000010877028

DTC B14XX AIR BAG DIAGNOSIS SENSOR UNIT

The air bag diagnosis sensor unit will run self diagnostics when the ignition switch is turned ON. It has the

potential to set many diagnostic trouble codes which will conform to the B14XX format, but will not match any

other SRS diagnostic trouble codes. Refer to 

SRC-13, "CONSULT Function"

.

PART LOCATION

Refer to 

SRC-6, "Component Parts Location"

.

DTC Description

INFOID:0000000010877029

DTC DETECTION LOGIC 

POSSIBLE CAUSE

Malfunction in air bag diagnosis sensor unit

FAIL-SAFE

—

DTC CONFIRMATION PROCEDURE (With CONSULT)

1.

CHECK SELF-DIAG RESULT

1. Turn ignition switch ON.

2. Check for DTC using CONSULT.
Is the DTC detected?

YES (Current DTC)>>Refer to 

SRC-105, "Diagnosis Procedure"

.

YES (Past DTC)>>GO TO 2.

DTC

CONSULT screen items

DTC detecting condition

B1400–00

CONTROL UNIT [UNIT MALFUNC]

Air bag diagnosis sensor unit is malfunctioning

B1401–00

B1402–00

B1403–00

B1404–00

B1405–00

B1406–00

B1407–00

B1408–00

B1409–00

B1410–00

B1411–00

B1412–00

B1413–00

B1414–00

B1415–00

B1416–00

B1417–00

B1418–00

B1419–00

B1420–00