Nissan Sentra. Manual - part 802

U1000 CAN COMM CIRCUIT

SRC-43

< DTC/CIRCUIT DIAGNOSIS >

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DTC/CIRCUIT DIAGNOSIS

U1000 CAN COMM CIRCUIT

Description

INFOID:0000000009757949

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 com-

munication 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 

LAN-30, "CAN

COMMUNICATION SYSTEM : CAN Communication Signal Chart"

.

DTC Logic

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DTC DETECTION LOGIC

DTC CONFIRMATION PROCEDURE

1.

PERFORM SELF-DIAGNOSIS

1. Turn ignition switch ON and wait for 7 seconds or more. 

2. Using CONSULT, perform SELF-DIAGNOSIS RESULTS of AIR BAG. 

3. Check if any DTC is displayed in the self-diagnosis results. 
Is DTC detected?

YES

>> Refer to 

SRC-43, "Diagnosis Procedure"

. 

NO

>> Refer to 

GI-39, "Intermittent Incident"

.

Diagnosis Procedure

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1.

CHECK CAN COMMUNICATION SYSTEM

Check CAN communication system. Refer to 

LAN-16, "Trouble Diagnosis Flow Chart"

.

>> Inspection End.

CONSULT name

DTC

DTC detecting condition

Repair order

CAN COMMUNICATION FAILURE

U1000

When air bag diagnosis sensor unit is not 
transmitting or receiving CAN communi-
cation signals for 2 or more seconds.

Refer to 

SRC-43, "Diagnosis 

Procedure"

. 

SRC-44

< DTC/CIRCUIT DIAGNOSIS >

U1010 CONTROL UNIT (CAN)

U1010 CONTROL UNIT (CAN)

Description

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Air bag diagnosis sensor performs self-tests on key ON. If CAN communication failure within control unit is

detected, DTC is set.

DTC Logic

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DTC DETECTION LOGIC

DTC CONFIRMATION PROCEDURE

1.

PERFORM SELF-DIAGNOSIS

1. Turn ignition switch ON. 

2. Using CONSULT, perform SELF DIAGNOSIS RESULTS of AIR BAG.

3. Check if DTC is displayed in the self-diagnosis results. 
Is DTC detected?

YES

>> Refer to 

SRC-44, "Diagnosis Procedure"

.

NO

>> Inspection End.

Diagnosis Procedure

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1.

REPLACE AIR BAG DIAGNOSIS SENSOR UNIT

Replace air bag diagnosis sensor unit. Refer to 

SR-28, "Removal and Installation"

.

>> Inspection End.

CONSULT name

DTC

DTC detecting condition

Repair order

CAN CONTROL UNIT FAILURE

U1010

CAN communication error is detected in 
control unit.

Refer to 

SRC-44, "Diagnosis 

Procedure"

.

B0001, B0002 DRIVER AIRBAG MODULE

SRC-45

< DTC/CIRCUIT DIAGNOSIS >

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B0001, B0002 DRIVER AIRBAG MODULE

Description

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DTC B0001, B0002 DRIVER AIRBAG MODULE

The driver air bag module is dual stage and is wired to the air bag diagnosis sensor unit through the spiral

cable. The air bag diagnosis sensor unit will monitor for opens and shorts in detected lines to the driver air bag

module including the spiral cable.

PART LOCATION

Refer to 

SRC-5, "Component Parts Location"

.

DTC Logic

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DTC DETECTION LOGIC 

With CONSULT

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-46, "Diagnosis Procedure"

.

YES (Past DTC)>>GO TO 2.

NO

>> Inspection End.

2.

ERASE SELF-DIAG RESULT

Erase the DTC using CONSULT.

CONSULT name

DTC

DTC detecting condition

Repair order

DRIVER AIRBAG MODULE CIRCUIT 

[OPEN]

B0001

Driver air bag module circuit 
(DR1) is open
(including the spiral cable).

Refer to 

SRC-46, "Diagnosis Proce-

dure"

.

DRIVER AIRBAG MODULE CIRCUIT 

[VB-SHORT]

Driver air bag module circuit 
(DR1) is shorted to a power sup-
ply circuit
(including the spiral cable).

DRIVER AIRBAG MODULE CIRCUIT 

[GND-SHORT]

Driver air bag module circuit 
(DR1) is shorted to ground
(including the spiral cable).

DRIVER AIRBAG MODULE CIRCUIT 

[SHORT]

Driver air bag module circuits 
(DR1) are shorted to each other
(including the spiral cable).

DRIVER AIRBAG MODULE 2ND CIRCUIT 

[OPEN]

B0002

Driver air bag module circuit 
(DR2) is open
(including the spiral cable).

DRIVER AIRBAG MODULE 2ND CIRCUIT 

[VB-SHORT]

Driver air bag module circuit 
(DR2) is shorted to a power sup-
ply circuit
(including the spiral cable).

DRIVER AIRBAG MODULE 2ND CIRCUIT 

[GND-SHORT]

Driver air bag module circuit 
(DR2) is shorted to ground
(including the spiral cable).

DRIVER AIRBAG MODULE 2ND CIRCUIT 

[SHORT]

Driver air bag module circuits 
(DR2) are shorted to each other
(including the spiral cable).

SRC-46

< DTC/CIRCUIT DIAGNOSIS >

B0001, B0002 DRIVER AIRBAG MODULE

Can the DTC be erased?

YES

>> Inspection End.

NO

>> Refer to 

SRC-46, "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-17, "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 

SRC-46, "Diagnosis Procedure"

.

NO

>> Inspection End.

Diagnosis Procedure

INFOID:0000000009757957

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-39, "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.

CHECK SPIRAL CABLE CIRCUIT 

1. Turn ignition switch OFF.

2. Disconnect driver air bag module harness connectors and spiral cable harness connector.

3. Check continuity between driver air bag module harness connector and spiral cable connector.