Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
Circuit Description
2004 Toyota Matrix XR, FWD, StandardSECTION Circuit Description
WARNING: This page is about a different car, the 2003 Lexus LS 430. However, it is still accessible from the selected car via links, so may be relevant.
This DTC is detected when the Transponder key ECU does not detect the key unlock warning switch ON even with the ignition switch ON. (In normal condition, the key unlock warning switch should be ON when the ignition switch is ON.)
DTC CONDITION DETECTION CHART
| DTC No. | DTC Detecting Condition. | Trouble Area |
|---|---|---|
| B2780 | The key unlock warning switch On is not detected when the ignition switch is ON. |
|
RENDER: 1.0x
NO RELATED
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.