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:
Strg 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 steering angle sensor for
damage, bend and loose connection
(unit side and connector side).
Is the inspection result ...
Body sealing
Description
The following figure shows the areas which are sealed at the factory. Sealant
which has been applied to these
areas should be smooth and free from cuts or gaps. Care should be taken not to
apply an excess amount of
sealant and not to allow other unaffected parts to come into conta ...
B142A Ignition voltage
Description
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-5, "Component Parts Location" ...
