MULTIPLEX INTEGRATED CONTROL SYSTEM DESCRIPTION - CONTROL/FUNCTION
Self-Diagnostic Function
The MICU provides the self-diagnostic function for checking the communication and input systems.
Communication Check (Test Mode 1):
When the B-CAN BUS or the connection to the gauge control module is disconnected, an error code is shown with the number of blinks of the front individual map light and ceiling light.
Switch Input Check (Test Mode 2):
When the input of a switch or a sensor to the MICU changes, diagnosis of the input system can be performed on the basis of the front individual map light and ceiling light flashing count.
HDS Diagnostics
The HDS connects to the data link connector (DLC) to communicate with the vehicle's control units. This allows the HDS to retrieve DTCs, diagnostic data, and transmit forced commands during output function tests.
MULTIPLEX INTEGRATED CONTROL SYSTEM DESCRIPTION - FAILSAFE FUNCTION
Hardware Failsafe Control
When a CPU problem or an abnormal power supply voltage is detected, the MICU moves to the hardware failsafe mode, and each system output load is set to the pre-programmed failsafe value.
Software Failsafe Control
When any of the data from the B-CAN circuit cannot be received within a specified time, or an unusual combination of the data is recognized, the MICU moves to the software failsafe mode. The data that cannot be received is forced to a pre-programmed value.
MULTIPLEX INTEGRATED CONTROL SYSTEM DESCRIPTION - FUNCTIONAL CONTROL MICU
Power Supply Voltage Monitoring Function
The MICU monitors the power supply voltage (backup voltage). If the voltage drops below 10 V, the MICU does not store DTCs.
Prevention of Key Locked Inside Vehicle
The MICU controls of the door lock actuators based on inputs from each switch and B-CAN data.
Entry Lights Control System (Ceiling Light, Front Individual Map Light)
The MICU controls the interior lights based on inputs from each switch and B-CAN.
Cargo Area Light
The MICU controls the cargo area light based on inputs from each switch.
Interior Lights Auto-Off Timer (Ceiling Light, Front Individual Map Light)
The MICU controls the interior lights OFF based on inputs from each switch and B-CAN data.
Collision Detection Signal (CDS)
The MICU controls the door lock actuators based on inputs from ignition switch (IG1) and B-CAN data.
Power Door Locks
The MICU controls the door lock actuators based on inputs from each switch and B-CAN data.
Auto Power Door Locks (LOCK Operation)
The MICU controls the door lock actuators based on inputs from each switch and B-CAN data.
Auto Power Door Locks (UNLOCK Operation)
The MICU controls the door lock actuators based on inputs from each switch and B-CAN data.
Auto Power Door Locks (LOCK/UNLOCK Switching Function)
The MICU controls the door lock actuators based on inputs from each switch and B-CAN data.
Door Lock Response Operation
The MICU controls the door lock actuators based on door lock signal sent by B-CAN data.
Keyless Entry System (Door Lock)
The MICU controls the door lock actuators based on inputs from each switch and B-CAN data.
Keyless Entry System (Tailgate)
The MICU controls the tailgate release actuator based on inputs from each switch and B-CAN data.
Security Alarm System
The MICU controls the lighting system and the horn based on inputs from each switch and B-CAN data.
Keyless Answer Back
The MICU controls the turn signal/hazard warning lights based on keyless signal sent by B-CAN.
Security Answer Back
The MICU controls the turn signal/hazard warning lights based on keyless signal sent by B-CAN.
Answer Back Response Operation (Turn signal light)
The MICU controls the turn signal/hazard warning lights based on keyless signal sent by B-CAN.
Keyless PANIC Operation
The MICU controls the PANIC operation based on B-CAN data.
Car Finding Operation
The MICU controls the car finding operation based on B-CAN data.
Combination Light Switch
The MICU controls the lighting system based on inputs from the combination light switch.
Exterior Lights
The MICU controls the exterior lights based on combination light switch inputs sent by B-CAN data.
Headlight Auto OFF Function
The MICU controls the lighting system based on inputs from each switch and B-CAN data.
Automatic Lighting System
The MICU controls the automatic lighting system based on inputs from IG1 switch and B-CAN data.
Daytime Running Lights
The MICU controls the headlights daytime running lights based on inputs from each switch and B-CAN data.
Front Fog Lights
The MICU controls the front fog lights based on inputs from combination light switch.
Turn Signal/Hazard Warning Lights
The MICU controls the turn signal/hazard warning lights based on inputs from each switch and the hazard warning switch.
One-Push Turn Signals
The MICU controls the turn signal lights based on inputs from combination light switch.
Windshield Wiper Switch
The MICU controls the wiper system based on inputs from each switch.
Windshield Wiper
The MICU controls the windshield wiper based on inputs from each switch and B-CAN data.
Rear Window Wiper Switch
The MICU controls the rear window wiper system based on inputs from rear window wiper switch.
Rear Window Wiper Operation
The MICU controls the rear window wiper based on inputs from each switch and B-CAN data.
Washer Operation
The MICU controls the windshield washer motor based on inputs from each switch.
Power Window Relay
The MICU controls the power window key-off operation based on inputs from ignition switch and B-CAN data.
Key Interlock (CVT)
The MICU controls the key interlock solenoid based on inputs from each switch.
A/C Switch
The MICU controls the A/C switch signal based on inputs from each switch.
Rear Window Defogger Switch
The MICU controls the rear window defogger signal based on inputs from each switch.
Heated Windshield Wiper Area Operation
The MICU controls the heated windshield wiper area based on inputs from each switch and B-CAN data.
FOB ID Transmission Operation
The MICU controls the FOB ID transmission based on inputs from each switch and B-CAN data.
MULTIPLEX INTEGRATED CONTROL SYSTEM DESCRIPTION - OVERVIEW
The MICU (built into the under-dash fuse/relay box) is one of the B-CAN components. The MICU controls many systems related to the body controller area and security system and also works as a gateway to diagnose other B-CAN connected ECUs with the HDS.