TSX L4-2.4L (2005)
Keyless Entry: Description and Operation
System Description
System Description
Security Alarm System
The security alarm system is armed automatically after the doors, hood, and trunk are closed and locked. For the system to arm, the ignition switch must
be off, the key must be removed, and the MICU must receive signals that the doors, hood, trunk are closed and locked. The alarm can be disarmed at any
time by unlocking the driver's door with the key or pressing the UNLOCK button on the remote transmitter.
When everything is closed and locked, the only inputs that are grounded, and have 0 V, are the driver's door lock knob switch (LOCK position), and the
integrated audio-HVAC display module. In other words, all of the other switches are open, and have about 0.8 V - 5.0 V, including the key cylinder
switches. The security indicator in the gauge control module begins to flash immediately after the vehicle is completely closed and locked, and 15
seconds later, the security system arms and the security indicator flashes on for a shorter amount of time than before. If the security indicator does not
flash, the system is not arming. A beep sounds and parking lights flash to confirm the security alarm system is armed if the LOCK button is pressed a
second time within 5 seconds.
If one of the switches is misadjusted or shorted internally, or there is a short in the circuit, the security system will not arm. As long as the control unit
continues to receive a ground signal (0 V), it senses that the vehicle is not closed and locked, and the system will not arm. A switch that is slightly
misadjusted can cause the alarm to sound for no apparent reason. In this case, a significant change in outside air temperature, the vibration of a passing
truck, or someone bumping into the vehicle could cause the alarm to sound. There is no glass breakage or motion detector feature.
If anything is opened or improperly unlocked after the system is armed, the control unit receives a ground signal from that switch, and the 10 V reference
drops to 0 V. If the integrated audio-HVAC display unit is disconnected, the input loses its ground, and the input voltage goes to 10 V. The system
sounds the alarm when any of these occur:
-
A door or the trunk is forced open
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A door is unlocked without using the key or the remote transmitter
-
The hood is opened
-
The audio-HVAC display unit is disconnected
-
The remote panic is operated
When the system sounds the alarm, the horns sound and the exterior lights flash for 2 minutes. The alarm can be stopped at any time by unlocking the
driver's door with the key or by pressing any button on the remote transmitter.
Panic Mode
The panic mode sounds the alarm in order to attract attention. When the PANIC button on the remote transmitter is pressed and held for 2 seconds, the
alarm sounds and the exterior lights flash for about 20 seconds.
The panic mode can be cancelled at anytime by pressing any button on the remote transmitter or by turning the ignition switch ON (II). The panic mode
will not function if the ignition switch is ON (II).
Keyless Entry System
The keyless entry system is integrated with the MICS. The multiplex integrated control unit (MICU) receives LOCK, UNLOCK and PANIC signals
from the door multiplex control unit (keyless receiver).
The keyless entry system allows you to lock and unlock the vehicle with the remote transmitter. When you press the LOCK button, all doors lock. When
you press the UNLOCK button once, only the driver's door unlocks. The other doors will unlock when you press the button a second time. The doors
will not lock with the remote transmitter if a door is not fully closed, or if the key is in the ignition switch.
If the UNLOCK button is pressed, released, then pressed and held, the windows will begin to open. The windows stop if the button is released. See
power windows for more information and troubleshooting.
When the switch for the ceiling light is in the center position, it will come on when the UNLOCK button is pressed. If a door is not opened, the light will
go off in about 30 seconds, and the doors will relock. If the doors are locked with the remote transmitter within 30 seconds, the light will go off
immediately.
