Nissan Sentra Service Manual: 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.
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:
Diagnosis system (bcm) (without intelligent
key system)
Common item
Common item : consult function (bcm -
common item)
APPLICATION ITEM
CONSULT performs the following functions via CAN communication with BCM.
Direct Diagnostic Mode
Description
ECU identification
The BCM part number is displayed.
Self Diagnostic Result
...
B0028 Side airbag module RH
Description
DTC B0028 FRONT RH SIDE AIR BAG MODULE
The front RH side air bag module is wired to the air bag diagnosis sensor
unit. The air bag diagnosis sensor
unit will monitor for opens and shorts in detected lines to the front RH side
air bag module.
PART LOCATION
Refer to SRC-5, " ...
Under cover
Front under cover
Front under cover : removal and installation
REMOVAL
Remove front side of front fender protector (LH/RH). Refer to EXT-28,
"FENDER PROTECTOR : Removal
and Installation - Front Fender Protector".
Remove engine under cover. EXT-31, "ENGINE UNDER COVER : Re ...
