Diagnosis System

1. Using Techstream, select "CAN Bus Check" from the "System Select".

1. Systems (ECUs, sensors) that use CAN communication vary depending on the vehicle's optional equipment. Check which systems (ECUs, sensors) are installed on the vehicle.
   ECU AND SENSOR REFERENCE
   
   

   ECU/Sensor name	Check method
   ABS/VSC/TRC	Installed on all vehicles
   STEERING SENSOR	With VSC system
   YAW/DECELERAT	With VSC system
   ENGINE	Installed on all vehicles
   ECT	With automatic transaxle
   SRS AIRBAG	Installed on all vehicles
   A/C	Installed on all vehicles
   METER	Installed on all vehicles
   MAIN BODY	Installed on all vehicles
   ACCESSORY GATEWAY	With dealer option
   SMART ACCESS/KEY	With smart key system

HINT:

• For the CAN communication system, CAN communication system DTCs stored in certain ECUs can be displayed using Techstream.
• If CAN communication system DTCs are output, trouble cannot be determined only by the DTCs. Perform troubleshooting according to "HOW TO PROCEED WITH TROUBLESHOOTING " .

1. ECM (2AZ-FE)
   DTC REFERENCE
   
   

   DTC No.	Detection Item
   U0101*	High speed CAN Communication Bus
   HINT: DTC communication is via the CAN communication system. *: The ECM is malfunctioning if only U0101 is output. Replace the ECM.

2. ECM(2GR-FE)
   DTC REFERENCE
   
   

   DTC No.	Detection Item
   U0101*	High speed CAN Communication Bus
   HINT: DTC communication is via the CAN communication system. *: The ECM is malfunctioning if only U0101 is output. Refer to DTC U0101 LOST COMMUNICATION WITH TCM SFI system .

3. ECT(2AZ-FE)
   DTC REFERENCE
   
   

   DTC No.	Detection Item
   U0100*	High speed CAN Communication Bus
   HINT: DTC communication is via the CAN communication system. *: The ECM is malfunctioning if only U0100 is output. Replace the ECM.

4. ECT(2GR-FE)
   DTC REFERENCE
   
   

   DTC No.	Detection Item
   U0100*	High speed CAN Communication Bus
   HINT: DTC communication is via the CAN communication system. *: The ECM is malfunctioning if only U0100 is output. Refer to DTC U0100 LOST COMMUNICATION WITH ECM/PCM "A" Automatic Transaxle system .

5. SKID CONTROL ECU (with VSC)
   DTC REFERENCE
   
   

   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
   HINT: DTC communication is via the CAN communication system. *: TMC made only

6. SKID CONTROL ECU (without VSC)
   DTC REFERENCE
   
   

   DTC No.	Detection Item
   U0073	Control Module Communication Bus Off

   HINT:

   DTC communication is via the CAN communication system.

7. COMBINATION METER ECU
   DTC REFERENCE
   
   

   DTC No.	Detection Item
   U0100	Lost Communication With ECM/PCM "A"
   U0129	Lost Communication with Brake System Control Mode

   HINT:

   DTC communication is via the CAN communication system.

8. AIR CONDITIONER AMPLIFIER
   DTC REFERENCE
   
   

   DTC No.	Detection Item
   B1499	Multiplex Communication Circuit

   HINT:

   DTC communication is via the CAN communication system.

9. MAIN BODY ECU (with smart key system)
   DTC REFERENCE
   
   

   DTC No.	Detection Item
   B1207*	Certification ECU Communication Malfunction
   B2326*	CAN MS Bus Line Communication Malfunction
   HINT: DTC communication is via the CAN communication system. *: The main body ECU is malfunctioning if B1207 and/or B2326 are output alone. Refer to DIAGNOSTIC TROUBLE CODE CHART .

10. MAIN BODY ECU (without smart key system)

    HINT:

    Although the center airbag sensor is connected to the CAN communication system, CAN communication DTCs are not output.

11. CENTER AIRBAG SENSOR

    HINT:

    Although the center airbag sensor is connected to the CAN communication system, CAN communication DTCs are not output.

12. CERTIFICATION ECU

    HINT:

    Although the Main Body ECU is connected to the CAN communication system, CAN communication DTCs are not output.

1. With VSC SYSTEM
   DTC REFERENCE
   
   

   DTC		Trouble Mode
   Output from	Output DTC	ECM Communication Stop Mode	Skid Control ECU Communication Stop Mode	Steering Angle Sensor Communication Stop Mode	Yaw Rate Sensor Communication Stop Mode
   Skid Control ECU	U0073	X	X	X	X
   	U0100	[Δ] During driving	[Δ] During driving	X	X
   	U0123	X	◦	X	◦
   	U0124(1)	X	◦	X	◦
   	U0126	X	◦	◦	X
   Combination Meter ECU	U0100	◦	X	X	X
   	U0129	X	◦	X	X
   Air Conditioner Amplifier ECU	B1499	X	X	X	X
   No DTC		X	X	X	X
   HINT: ◦: Set X: Not set or may be set according to the malfunctioning part when one side of the CAN bus wire opens Δ : Set under the condition shown in the table above
   (1) TMC made only.

   DTC REFERENCE
   
   

   DTC		Trouble Mode
   Output from	Output DTC	Air Conditioner Amplifier ECU Communication Stop Mode	Center Airbag Sensor Communication Stop Mode	Main Body ECU Communication Stop Mode	Combination Meter ECU Communication Stop Mode
   Skid Control ECU	U0073	X	X	X	X
   	U0100	X	X	X	X
   	U0123	X	X	X	X
   	U0124(1)	X	X	X	X
   	U0126	X	X	X	X
   Combination Meter ECU	U0100	X	X	X	X
   	U0129	X	X	X	X
   Air Conditioner Amplifier ECU	B1499	X	X	Δ	Δ
   No DTC		◦	◦	X	X
   HINT: ◦: Set X: Not set or may be set according to the malfunctioning part when one side of the CAN bus wire opens Δ : The combination meter and main body ECU indicate communication errors.
   (1) TMC made only.

2. Without VSC SYSTEM
   DTC REFERENCE
   
   

   DTC		Trouble Mode
   Output from	Output DTC	ECM Communication Stop Mode	Skid Control ECU Communication Stop Mode	Combination Meter ECU Communication Stop Mode	Air Conditioner Amplifier ECU Communication Stop Mode	Center Airbag Sensor Communication Stop Mode	Main Body ECU Communication Stop Mode
   Skid Control ECU	U0073	X	X	X	X	X	X
   Combination Meter ECU	U0100	◦	X	X	X	X	X
   	U0129	X	◦	X	X	X	X
   Air Conditioner Amplifier ECU	B1499	X	X	Δ	X	X	Δ
   No DTC		X	X	X	◦	◦	X
   HINT: ◦: Set X: Not set or may be set according to the malfunctioning part when one side of the CAN bus wire becomes open. Δ: The combination meter and main body ECU indicate communication errors.

3. Perform troubleshooting depending on the combination of DTCs output.

   HINT:

   • ECM Communication Stop Mode (See ECM COMMUNICATION STOP MODE  )
   • Skid Control ECU Communication Stop Mode (See SKID CONTROL ECU COMMUNICATION STOP MODE  )
   • Steering Angle Sensor Communication Stop Mode (See STEERING ANGLE SENSOR COMMUNICATION STOP MODE  )
   • Yaw Rate Sensor Communication Stop Mode (See YAW RATE SENSOR COMMUNICATION STOP MODE  )
   • Combination Meter ECU Communication Stop Mode (See COMBINATION METER ECU COMMUNICATION STOP MODE  )
   • Center Airbag Sensor Communication Stop Mode (See CENTER AIRBAG SENSOR COMMUNICATION STOP MODE  )
   • Air Conditioner Amplifier ECU Communication Stop Mode (See AIR CONDITIONING AMPLIFIER COMMUNICATION STOP MODE  )
   • Main Body ECU Communication Stop Mode (See MAIN BODY ECU COMMUNICATION STOP MODE  )