Description
CAN (Controller Area Network) is a serial communication line for real time application. It is an on-vehicle multiplex communication line with high data communication speed and excellent error detection ability. Many electronic control units are equipped onto a vehicle, and each control unit shares information and links with other control units during operation (not independent). In CAN communication, control units are connected with 2 communication lines (CAN H line, CAN L line) allowing a high rate of information transmission with less wiring.
Each control unit transmits/receives data but selectively reads required data only.
DTC Description
DTC DETECTION LOGIC
| DTC No. | CONSULT screen terms (Trouble diagnosis content) | DTC detecting condition |
| U1001 | CAN COMM CIRCUIT (CAN COMM CIRCUIT) | When ECM is not transmitting or receiving CAN communication signal other than OBD (emission related diagnosis) for 2 seconds or more. |
POSSIBLE CAUSE
Harness or connectors (CAN communication line is open or shorted)
FAIL-SAFE
Not applicable
DTC CONFIRMATION PROCEDURE
1.PERFORM DTC CONFIRMATION PROCEDURE
Is 1st trip DTC detected? YES >> Proceed to EC-170, "Diagnosis Procedure".
NO >> INSPECTION END
Diagnosis Procedure
Perform the trouble diagnosis for CAN communication system. Refer to LAN-17, "Trouble Diagnosis Flow Chart".
U0101 CAN comm circuit
U1040 ENG comm circuitAir bag diagnosis sensor unit
Exploded View
Diagnosis sensor unit
Front
Removal and Installation
WARNING:
Before servicing the SRS, turn ignition switch OFF, disconnect
both battery terminals then wait at
least three minutes.
Before disconnecting the air bag diagnosis sensor unit harness
...
Wiring diagram
BCM
Wiring Diagram
...
System
System Description
SYSTEM DIAGRAM
OPERATION DESCRIPTION
When rear window defogger switch is turned ON while ignition
switch is ON, the rear window defogger
switch transmits rear window defogger switch signal to BCM.
BCM turns rear window defogger relay ON when rear windo ...