Nissan Sentra Service Manual: U1000 CAN Comm circuit

Nissan Sentra Service Manual / Restraints / SRS airbag control system / DTC/Circuit diagnosis / U1000 CAN Comm circuit

Description

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 communication 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

DTC DETECTION LOGIC

CONSULT name	DTC	DTC detecting condition	Repair order
CAN COMMUNICATION FAILURE	U1000	When air bag diagnosis sensor unit is not transmitting or receiving CAN communication signals for 2 or more seconds.	Refer to SRC-43, "Diagnosis Procedure".

DTC CONFIRMATION PROCEDURE

1.PERFORM SELF-DIAGNOSIS

Turn ignition switch ON and wait for 7 seconds or more.
Using CONSULT, perform SELF-DIAGNOSIS RESULTS of AIR BAG.
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

1.CHECK CAN COMMUNICATION SYSTEM

Check CAN communication system. Refer to LAN-16, "Trouble Diagnosis Flow Chart".

>> Inspection End.

DTC/Circuit diagnosis

...

U1010 Control unit (CAN)

Description Air bag diagnosis sensor performs self-tests on key ON. If CAN communication failure within control unit is detected, DTC is set. DTC Logic DTC DETECTION LOGIC CONSULT name ...

Other materials:

Ecu diagnosis information
Ipdm e/r (intelligent power distribution module engine room) Reference Value Values on the diagnosis tool Terminal layout Physical values Fail-Safe Can communication control When can communication with ecm and bcm is impossible, ipdm e/r performs fail-safe ...

M&A 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 combination meter for damage, bend and loose connection (unit side and connector side). Is the inspection result nor ...

Electrical load signal
Description The electrical load signal (Headlamp switch signal, rear window defogger switch signal, etc.) is transferred via the CAN communication line. Component Function Check 1.CHECK REAR WINDOW DEFOGGER SWITCH FUNCTION With CONSULT Turn ignition switch ON. Select вЂњDATA MONITOR� ...