STA Signal Circuit [12/2024 - ]: Description

2025 Toyota 4Runner SR5, 4WDSECTION Description

While the engine is being cranked, a starter operation request signal is sent to terminal STA of the ECM.

HINT: 

If there is an open in the STA circuit of the ECM, stop and start control will be prohibited after the third time the engine is started by stop and start control.

  • Stop and start control will be prohibited until the ignition switch is turned off.
  • The MIL will illuminate.
  • If there is an open in the STA circuit of the ECM, the engine can still be started using the ignition switch, as the ECM also receives the starter operation request signal from the engine stop and start ECU via CAN communication. (Stop and start control is prohibited as the reliability of the signal sent via CAN communication cannot be assured while the voltage drops during operation of the starter assembly.)
GTY1271041Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
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:

  • You smell fuel, burning insulation, or see smoke.
  • Brakes feel soft, pull hard to one side, or make grinding noises.
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