MICU Control Functions Index
The driver's MICU (built into the driver's under-dash fuse/relay box) is one of the B-CAN components. The driver's MICU controls many systems related to the body controller area and a security system, and also works as a gateway to diagnose the other B-CAN connected ECUs with the HDS.
Refer to each system circuit diagram for details.
System
Function
Multiplex Control
Sends the switch input signal information to the driver's MICU and outputs the information. The driver's MICU controls the ECUs electric load and communication based upon the information received the B-CAN.
On-Board Diagnosis
The driver's MICU has a gateway function which sends the results of the driver's MICU internal diagnosis and the B-CAN connected ECU's diagnosis to the HDS.
Self-Diagnosis
Test mode 1 diagnoses the communication line between the driver's MICU and B-CAN connected units. Test mode 2 check the switch and sensor circuits connected to the driver's MICU. Some switch and sensor circuits connected to the passenger's MICU, door multiplex control unit, and front passenger's power window switch can check also when the B-CAN line is normal.
Interior Light(s)
The driver's MICU controls the interior lights ON, OFF and dimming based upon the information of the related switches and/or the B-CAN related information.
Sleep Function
The driver's MICU has a sleep function, which it enters during the power down mode.

The driver's MICU also controls the function of these circuits: