The following warning indicates the possibility of damage to the vehicle that may lead to an accident. Immediately stop the vehicle in a safe place and contact your Toyota dealer.

Stop the vehicle immediately. Continuing to drive the vehicle may be dangerous.
Have the vehicle inspected immediately.Horn Circuit
DESCRIPTION
When the theft deterrent system is switched from the armed state to the alarm
sounding state, the main body ECU (driver side junction block assembly) transmits
a signal to cause the horn to sound at intervals of 0.4 seconds.
WIRING DIAGRAM
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Installation
INSTALLATION
PROCEDURE
1. REPAIR INSTRUCTION
(a) Clean the vehicle body surface.
(1) Using a heat light, heat the vehicle body surface.
Heating Temperature
Item
Temperature
Vehicle Body
40 to 60°C (104 t ...
Sound Signal Circuit between Navigation Receiver Assembly and Stereo Component
Amplifier
DESCRIPTION
The navigation receiver assembly sends a sound signal to the stereo component
amplifier assembly via this circuit.
The sound signal that has been sent is amplified by the stereo component amplifier
assembly, and then is sent to the speakers.
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