Key Reminder System

2004 Toyota Matrix XR, FWD, StandardSECTION Key Reminder System
WARNING: This page is about a different car, the 2003 Lexus RX 300 and 2002 Lexus RX 300. However, it is still accessible from the selected car via links, so may be relevant.

If the driver door is opened with the ignition switch set at the ACC or OFF position and the ignition key remained inserted into the key cylinder (the unlock warning switch is on), the signal from the unlock warning switch is input to terminal KSW of the body ECU and the signal from the front LH door courtesy switch is input to terminal CTY of driver door ECU. See WIRING DIAGRAMSΒ . As a result, through communication control of the body ECU and door ECU etc. the buzzer in the combination meter goes on to warn the driver that the ignition key is still inserted.

RENDER: 1.0x

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • β€’ You smell fuel, burning insulation, or see smoke.
  • β€’ Brakes feel soft, pull hard to one side, or make grinding noises.
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  • β€’ You are not confident in the next step or safety outcome.