Can Communication System -- Diagnosis System |
BUS CHECK (COMMUNICATION MALFUNCTION DTC) |
- HINT:
- Only CAN communication system DTCs for each ECU can be displayed on the intelligent tester.
Select "Bus Check" from the "System select" screen on the intelligent tester.
Select "Communication Malfunction DTC" from the "Bus Check" screen, and then select "Enter".
Select the system of the DTC to be checked and select "Details".
CAN communication system DTC(s) is/are displayed.
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BUS CHECK (COMMUNICATION BUS CHECK) |
- HINT:
- The ECUs and sensors that are properly connected to the CAN communication system can be displayed using the intelligent tester.
Select "Communication Bus Check" from the "Bus Check" screen.
The screen displays the ECUs and sensors that are properly connected to the CAN communication system.
- HINT:
- There is a communication stop in the system of any properly connected ECUs or sensors that are not displayed (Click here).
"There is no system connected to the communication bus" is displayed if there are no ECUs or sensors connected to the CAN bus.
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CHECK FOR INSTALLED SYSTEMS (ECUS & SENSORS) THAT ADOPT CAN COMMUNICATION |
Systems (ECUs, sensors) that adopt CAN communication vary depending on the vehicle's optional settings. Check which systems (ECUs, sensors) are installed on the vehicle.
ECU/Sensor name Check method Skid control ECU with actuator Engine model 3GR-FE or 3GR-FSE Skid control ECU Engine model 3UZ-FE Steering sensor Installed on all vehicles Yaw rate sensor Installed on all vehicles ECM Installed on all vehicles Distance control ECU Dynamic radar cruise control Absorber control ECU Engine model 3UZ-FE Network gateway ECU Installed on all vehicles Television camera ECU Parking assist monitor system Clearance warning ECU LEXUS parking assist-sensor Seat belt control ECU Dynamic radar cruise control Power steering ECU Installed on all vehicles Steering control ECU Engine model 3UZ-FE
DTC TABLE BY ECU |
- HINT:
- In the CAN communication system, CAN communication system DTCs can be displayed by the ECU using the intelligent tester.
- If CAN communication system DTCs are output, trouble cannot be determined only by the DTCs. Perform troubleshooting according to "HOW TO PROCEED WITH TROUBLESHOOTING "(Click here). (If, however, U0235 or U1101/U01102 is output alone, see the dynamic radar cruise control system.)
ECM
- HINT:
- DTC communication uses the CAN communication system.
- Distance control ECU data is also output.
DTC No. Detection Item U0001(*1) High speed CAN Communication Bus U0100 Lost Communication With ECM/PCM "A" U0122 Lost Communication With Vehicle Dynamics Control Module U0123 Lost Communication With Yaw Rate Sensor Module U0126 Lost Communication With Steering Angle Sensor Module U0235(*2) Lost Communication With Cruise Control Front Distance Range Sensor U1101(*3) Lost Communication With Distance Control ECU U1102(*2) Lost Communication With Distance Control ECU
- *1: The ECM is malfunctioning if U0001 is output alone. Replace the ECM.
- *2: Displayed on the "communication malfunction DTCs "screen of the intelligent tester. If U0235 or U1102 is output alone, the CAN communication is normal (Click herefor U0235, Click here for U1102).
- *3: Dynamic radar cruise DTC.
SKID CONTROL ECU
- HINT:
- DTC communication uses the SIL line.
DTC No. Detection Item U0073 Control Module Communication Bus Off U0100 Lost Communication With ECM/PCM "A" U0123 Lost Communication With Yaw Rate Sensor Module U0124 Lost Communication With Lateral Acceleration Sensor Module U0126 Lost Communication With Steering Angle Sensor Module U0130 Lost communication With Steering control Module U0131 Lost communication With Power Steering U1101 Lost communication With Distance Control Module ABSORBER CONTROL ECU
- HINT:
- DTC communication uses the SIL line.
DTC No. Detection Item U0100 Lost Communication With ECM/PCM "A" U0101 Lost Communication With ECM U0122 Lost Communication With Vehicle Dynamics Control Module U0124 Lost Communication With Lateral Acceleration Sensor Module U0126 Lost Communication With Steering Angle Sensor Module POWER STEERING ECU
DTC No. Detection Item U0073 Control Module Communication Bus Off U0105 Lost Communication With ECM/PCM "A" U0121 Lost Communication With Skid Control ECU U0122 Lost Communication With Skid Control ECU/ Skid Control ECU with actuator U0104 Lost Communication With Vehicle Dynamics Control Module U0130 Lost Communication With Power Steering ECU SEAT BELT CONTROL ECU
DTC No. Detection Item U0100 Lost Communication With ECM/PCM "A" U0122 Lost Communication With Vehicle Dynamics Control Module U0145 Lost Communication With Gateway ECU U1101 Lost Communication With Distance Control ECU DISTANCE CONTROL ECU
DTC No. Detection Item U0100 Lost Communication With ECM/PCM "A" U0122 Lost Communication With Vehicle Dynamics Control Module U0123 Lost Communication With Yaw Rate Sensor Module U0131 Lost Communication With Power Steering ECU U0132 Lost Communication With Absorber Control ECU U0146 Lost Communication With Gateway ECU U1101 Lost Communication With Distance Control ECU STEERING CONTROL ECU
DTC No. Detection Item U0100 Lost Communication With ECM/PCM "A" U0122 Lost Communication With Vehicle Dynamics Control Module U0126 Lost Communication With Steering Sensor Module U0131 Lost Communication With Power Steering ECU TELEVISION CAMERA ECU
- HINT:
- The television camera ECU is connected to the CAN communication system but CAN communication system DTCs are not output.
NETWORK GATEWAY ECU
- HINT:
- The network gateway ECU is connected to the CAN communication system but CAN communication DTCs are not output.
DTC COMBINATION TABLE |
DTC | Trouble Mode | ||||||
Output from | Output DTC | SKID CONTROL ECU COMMUNICATION STOP MODE | STEERING SENSOR COMMUNICATION STOP MODE | YAW RATE SENSOR COMMUNICATION STOP MODE | GATEWAY ECU COMMUNICATION STOP MODE | ECM COMMUNICATION STOP MODE | DISTANCE CONTROL ECU COMMUNICATION STOP MODE |
Skid Control ECU | U0073 | X | X | X | X | X | X |
U0100 | ▲ During driving | X | X | X | ▲ During driving | X | |
U0123 | ○ | X | ○ | X | X | X | |
U0124 | ○ | X | ○ | X | X | X | |
U0126 | ○ | ○ | X | X | X | X | |
U0130 | X | X | X | X | X | X | |
U0131 | X | X | X | X | X | X | |
U1101 | X | X | X | X | X | ○ | |
Absorber Control ECU | U0100 | X | X | X | X | ○ | X |
U0101 | X | X | X | X | ○ | X | |
U0122 | ○ | X | X | X | X | X | |
U0124 | X | X | ○ | X | X | X | |
U0126 | X | ○ | X | X | X | X | |
Seat Belt Control ECU | U0100 | X | X | X | X | X | X |
U0122 | ○ | X | X | X | X | X | |
U0146 | X | X | X | ○ | X | X | |
U1101 | X | X | X | X | X | ○ | |
ECM | U0100 | X | X | X | X | X | X |
U0122 | ▲ Control distance | X | X | X | X | X | |
U0123 | X | X | ▲ Control distance | X | X | X | |
U0126 | X | ▲ Control distance | X | X | X | X | |
U1101 | X | X | X | X | X | ○ | |
U1102 | X | X | X | X | ○ | X | |
U0235 | X | X | X | X | ○ | X | |
○: Output ▲: Output under the following condition X: Not output or may be output according to the malfunctioning part when one side of the CAN bus line opens |
DTC | Trouble Mode | |||||
Output from | Output DTC | ABSORBER CONTROL ECU COMMUNICATION STOP MODE | TELEVISION CAMERA ECU COMMUNICATION STOP MODE | SEAT BELT CONTROL ECU COMMUNICATION STOP MODE | POWER STEERING ECU COMMUNICATION STOP MODE | STEERING CONTROL ECU COMMUNICATION STOP MODE |
Skid Control ECU | U0073 | X | X | X | X | X |
U0100 | X | X | X | X | X | |
U0123 | X | X | X | X | X | |
U0124 | X | X | X | X | X | |
U0126 | X | X | X | X | X | |
U0130 | X | X | X | X | ○ | |
U0131 | X | X | X | ○ | X | |
U1101 | X | X | X | X | X | |
Absorber Control ECU | U0100 | ○ | X | X | X | X |
U0101 | ○ | X | X | X | X | |
U0122 | ○ | X | X | X | X | |
U0124 | ○ | X | X | X | X | |
U0126 | ○ | X | X | X | X | |
Seat Belt Control ECU | U0100 | X | X | X | X | X |
U0122 | X | X | X | X | X | |
U0145 | X | X | X | X | X | |
U1101 | X | X | X | X | X | |
ECM | U0100 | X | X | X | X | X |
U0122 | X | X | X | X | X | |
U0123 | X | X | X | X | X | |
U0126 | X | X | X | X | X | |
U1101 | X | X | X | X | X | |
U1102 | X | X | X | X | X | |
U0235 | X | X | X | X | X | |
○: Output ▲: Output under the following condition X: Not output or may be output according to the malfunctioning part when one side of the CAN bus line opens |
DTC | Trouble Mode | ||||||
Output from | Output DTC | SKID CONTROL ECU COMMUNICATION STOP MODE | STEERING SENSOR COMMUNICATION STOP MODE | YAW RATE SENSOR COMMUNICATION STOP MODE | GATEWAY ECU COMMUNICATION STOP MODE | ECM COMMUNICATION STOP MODE | DISTANCE CONTROL ECU COMMUNICATION STOP MODE |
Power Steering ECU | U0073 | X | X | X | X | X | X |
U0105 | X | X | X | X | ○ | X | |
U0121 | ○ | X | X | X | X | X | |
U0122 | ○ 3UZ-FE | X | X | X | X | X | |
U0104 | X | X | X | X | X | ○ | |
U0130 | X | X | X | X | X | X | |
Distance Control ECU | U0100 | X | X | X | X | ▲ | X |
U0122 | ▲ | X | X | X | X | X | |
U0123 | X | X | ▲ | X | X | X | |
U0131 | X | X | X | X | X | X | |
U0132 | X | X | X | X | X | X | |
U0146 | X | X | X | X | X | X | |
U1101 | X | X | X | X | X | X | |
Steering Control ECU | U0100 | X | X | X | X | ○ | X |
U0122 | ○ | X | X | X | X | X | |
U0126 | X | ○ | X | X | X | X | |
U0131 | X | X | X | X | X | X | |
○: Output ▲: Output under the following condition X: Not output or may be output according to the malfunctioning part when one side of the CAN bus line opens |
DTC | Trouble Mode | |||||
Output from | Output DTC | ABSORBER CONTROL ECU COMMUNICATION STOP MODE | TELEVISION CAMERA ECU COMMUNICATION STOP MODE | SEAT BELT CONTROL ECU COMMUNICATION STOP MODE | POWER STEERING ECU COMMUNICATION STOP MODE | STEERING CONTROL ECU COMMUNICATION STOP MODE |
Power Steering ECU | U0073 | X | X | X | X | X |
U0105 | X | X | X | X | X | |
U0121 | X | X | X | X | X | |
U0122 | X | X | X | X | X | |
U0104 | X | X | X | X | X | |
U0130 | X | X | X | X | ○ | |
Distance Control ECU | U0100 | X | X | X | X | X |
U0122 | X | X | X | X | X | |
U0123 | X | X | X | X | X | |
U0131 | X | X | X | X | X | |
U0132 | X | X | X | X | X | |
U0146 | X | X | X | X | X | |
U1101 | X | X | X | X | X | |
Steering Control ECU | U0100 | X | X | X | X | X |
U0122 | X | X | X | X | X | |
U0126 | X | X | X | X | X | |
U0131 | X | X | X | ○ | X | |
○: Output ▲: Output under the following condition X: Not output or may be output according to the malfunctioning part when one side of the CAN bus line opens |
Perform troubleshooting according to the combination of DTCs output.
- HINT:
- ECM COMMUNICATION STOP MODE: Click here
- SKID CONTROL ECU COMMUNICATION STOP MODE: Click here
- SKID CONTROL ECU WITH ACTUATOR COMMUNICATION STOP MODE: Click here
- YAW RATE SENSOR COMMUNICATION STOP MODE: Click here
- STEERING SENSOR COMMUNICATION STOP MODE: Click here
- DISTANCE CONTROL ECU COMMUNICATION STOP MODE: Click here
- TELEVISION CAMERA ECU COMMUNICATION STOP MODE: Click here
- SEAT BELT CONTROL ECU COMMUNICATION STOP MODE: Click here
- STEERING CONTROL ECU COMMUNICATION STOP MODE: Click here
- ABSORBER CONTROL ECU COMMUNICATION STOP MODE: Click here
- NETWORK GATEWAY ECU COMMUNICATION STOP MODE: Click here
- POWER STEERING ECU COMMUNICATION STOP MODE: Click here
- CLEARANCE WARNING ECU COMMUNICATION STOP MODE: Click here