The Main Body ECU and Certification ECU perform 2-way communication with each other via the Controller Area Network (CAN). If the Certification ECU cannot communicate with the Main Body ECU, the Main Body ECU will conclude that there is a malfunction in the CAN system, and set a DTC.


DTC Detection Condition

Trouble Area

B1207 B2326

No communication from certification ECU continues

• CAN MS bus wire or connector

• Certification ECU power source circuit

• Certification ECU

• Main body ECU

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Do It Yourself Car Diagnosis

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