LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Lexus >> 2009 >> LS 600hL >> Repair and Diagnosis >> External Pages >> Different car >> Section 26 (Starting) >> Smart Access System With Push-Button Start >> Power Source Mode does not Change to ON (READY) >> Description
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Power Source Mode does not Change to ON (READY): Description

WARNING: This page is about a different car, the 2008 Lexus LS 600hL. However, it is still accessible from the selected car via links, so may be relevant.
  1. POWER SWITCH ON (READY) OPERATION 
    1. When the power switch is pressed with the brake pedal depressed and shift lever in P, the main body ECU determines that it is a hybrid control system start request.
    2. The certification ECU and other ECUs perform key verification via the LIN communication line The power switch indicator light illuminates in green.
    3. The main body ECU activates the D-IG1 relay, D-ACC relay and ignition relay No. 2 (IG2)
    4. The certification ECU outputs a steering UNLOCK signal The signal is sent to the steering lock ECU via the LIN communication line
    5. The main body ECU sends a power switch ON (READY) request signal to the hybrid vehicle control ECU
    6. The main body ECU deactivates the D-ACC relay until the ECU detects that the power switch is ON (READY)
    7. The ECU reactivates the D-ACC relay and turns OFF the power switch indicator light.
      MAIN BODY ECU SYMBOLS REFERENCE

      Symbols of main body ECU Signals
      SSW1/SSW2 Power switch ON (ACC, IG) signal
      IG1D D-IG1 relay operation signal
      ACCD D-ACC relay operation signal
      IG2D Ignition relay No 2 (IG2) operation signal
      STP Stop light switch signal
      P Shift lock signal
      RDY Power switch ON (READY) signal
      STSW Hybrid control system activation request signal
      Fig 1: Power Source Mode Communication Diagram
      G05780706Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002