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Multiplex Integrated Control System Sleep and Wake-Up Mode Test




Multiplex Integrated Control System Sleep and Wake-Up Mode Test

1. Shift to the sleep mode:

Close all doors. Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode, remove the key without keyless access system, then open and close the driver's door. If the MICU receives no signals from the inputs listed below, it will go into sleep mode in less than 50 seconds.

- IG1 power supply
- IG2 power supply
- B-CAN data
- Tailgate latch switch (Tailgate closed) (OFF)
- Hazard warning switch (OFF)

2. Confirm the sleep mode:

NOTE: Check any official Honda service website for more service information about parasitic draw at the battery.

Check the parasitic draw at the battery while shifting into the sleep mode; amperage should change from about 200 mA to less than 35 mA in less than 50 seconds.

3. Shift to the wake-up mode:

When the ignition switch is turned to ON (II), or the vehicle is in ON mode. The driver's MICU, the passenger's MICU, the gauge control module, the immobilizer-keyless control unit, and the PCM wake-up at the same time without "talking" to each other through the communication lines. When any switch in the multiplex integrated control system is turned on, it wakes up its related control unit which, in turn, wakes up the other units.
After confirming the MICU is in sleep mode, look in the following table for the switch most related to the problem. Operate that switch and see if its control unit wakes up.

NOTE: If any control unit is faulty and does not wake up, several circuits in the system malfunction at the same time. Below is a list of the switches and input signals that wake them up.

- IG1 power supply
- IG2 power supply
- B-CAN data
- Driver's door switch (door open)
- Left rear door switch (door open)
- Tailgate latch switch (Tailgate open)
- Tailgate outer handle switch (Tailgate open)
- Left rear door lock knob switch
- Security hood switch (hood open)
- Hazard warning switch (ON)
- Combination light switch (Parking, Headlight, Dimmer, Passing ON)
- Ignition key switch (key inserted)
- Driver's door key cylinder switch (LOCK/UNLOCK)
- Passenger's rear door lock knob (UNLOCK)
- Front passenger's door lock knob (UNLOCK)
- Driver's door lock switch (LOCK/UNLOCK)
- Front passenger's door lock switch (LOCK/UNLOCK)
- Front passenger's door switch (door open)
- Passenger's rear door switch (door open)