U121B AV CONTROL UNIT

Replace the AV control unit if this DTC is displayed. Refer to Exploded View.

Part name

Description

AV control unit

Integrates HDD (hard disk drive) allowing map data and music data to be stored. It is the master unit of the MULTI AV system, and it is connected to each control unit by means of communication. It operates each system according to communication signals from the AV control unit. The AV control unit includes the audio function, hand-free phone function, voice control function, navigation function, multifunction meter function, and vehicle information function. It is connected to ECM, combination meter, TCM, AWD control unit, steering angle sensor, ABS actuator and electric unit (control unit) with the CAN communication line to obtain necessary information for the multifunction meter function. It is connected to ECM, combination meter and A/C auto amp. with the CAN communication line to obtain necessary information for the vehicle information function. It is connected to BCM via CAN communication transmitting/receiving for the vehicle settings function. It is connected to low tire pressure warning control unit with the CAN communication line to obtain necessary information for the tire pressure status. It inputs the dimming signals that are required for the display dimming control. It inputs the signal for driving status recognition (vehicle speed signal, reverse signal, and parking brake signal). Update of map data is performed with the CONSULT-III and the applicable cable. It includes the TEL adapter and BluetoothTM function.

DTC	Display contents of CONSULT‐III	DTC Detection Condition	Action to take
U121B	HDD‐COMM [U121B]	Internal malfunction of AV control unit (HDD communication error) is detected.	Replace AV control unit.