LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Infiniti >> 2009 >> M45 Base >> Repair and Diagnosis >> External Pages >> Different car >> Section 154 (Supplemental Restraint System) >> Occupant Classification System >> Terminals Of Ecu
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Terminals Of Ecu

WARNING: This page is about a different car, the 2008 Toyota Tundra. However, it is still accessible from the selected car via links, so may be relevant.
  1. CHECK OCCUPANT CLASSIFICATION ECU 
    ECU TERMINAL REFERENCE TABLE

    Terminal No. (Symbols) Wiring Color Terminal Description Condition Specification
    Y2-1 (+B) - Y2-3 (GND)*1
    Q11-1 (+B) - Q11-3 (GND)*2
    R - W-B Battery Ignition switch ON 11 to 14 V
    Y2-2 (DIA) - Y2-3 (GND)*1
    Q11-2 (DIA) - Q11-3 (GND)*2
    BR - W-B Diagnosis (DLC3) Ignition switch ON Pulse generation
    Y2-3 (GND) - Body ground*1
    Q11-3 (GND) - Body ground*2
    W-B - Body ground Ground Always Below 1 Ω
    Y2-4- (FSR-) - Y2-3 (GND)*1
    Q11-4- (FSR-) - Q11-3 (GND)*2
    B - W-B Center airbag sensor communication ground line Always Below 1 Ω
    Y2-5 (BGND) - Y2-3 (GND)*1
    Q11-5 (BGND) - Q11-3 (GND)*2
    O - W-B Passenger side buckle switch ground line Always Below 1 Ω
    Y2-7 (IG) - Y2-3 (GND)*1
    Q11-7 (IG) - Q11-3 (GND)*2
    SB - W-B Power source (IGN fuse) Ignition switch ON 11 to 14 V
    Y2-8 (FSR+) - Y2-4 (FSR-)*1
    Q11-8 (FSR+) - Q11-4 (FSR-)*2
    W - B Center airbag sensor communication line Ignition switch ON Pulse generation
    Y2-9 (BSW) - Y2-5 (BGND)*1
    Q11-9 (BSW) - Q11-5 (BGND)*2
    L - O Passenger side buckle switch line Buckle switch ON 0.12 to 0.18 A
    Buckle switch OFF 0.4 to 0.7 mA
    Y1-1 (SGD1) - Y2-3 (GND)*1
    Y1-1 (SGD1) - Q11-3 (GND)*2
    Y - W-B Front occupant detection sensor LH ground line Always Below 1 Ω
    Y1-2 (SGD2) - Y2-3 (GND)*1
    Y1-2 (SGD2) - Q11-3 (GND)*2
    SB - W-B Front occupant detection sensor RH ground line Always Below 1 Ω
    Y1-3 (SGD3) - Y2-3 (GND)*1
    Y1-3 (SGD3) - Q11-3 (GND)*2
    L - W-B Rear occupant detection sensor LH ground line Always Below 1 Ω
    Y1-4 (SGD4) - Y2-3 (GND)*1
    Y1-4 (SGD4) - Q11-3 (GND)*2
    W - W-B Rear occupant detection sensor RH ground line Always Below 1 Ω
    Y1-11 (SVC1) - Y1-1 (SGD1) P - Y Front occupant detection sensor LH power supply line Ignition switch ON, load is applied to front occupant detection sensor LH 4.5 to 5.1 V
    Y1-12 (SVC2) - Y1-2 (SGD2) BR - SB Front occupant detection sensor RH power supply line Ignition switch ON, load is applied to front occupant detection sensor RH 4.5 to 5.1 V
    Y1-5 (SVC3) - Y1-3 (SGD3) R - L Rear occupant detection sensor LH power supply line Ignition switch ON, load is applied to rear occupant detection sensor LH 4.5 to 5.1 V
    Y1-6 (SVC4) - Y1-4 (SGD4) B - W Rear occupant detection sensor RH power supply line Ignition switch ON, load is applied to rear occupant detection sensor RH 4.5 to 5.1 V
    Y1-7 (SIG1) - Y1-1 (SGD1) O - Y Front occupant detection sensor LH signal line Ignition switch ON, load is applied to front occupant detection sensor LH Pulse generation
    Y1-8 (SIG2) - Y1-2 (SGD2) GR - SB Front occupant detection sensor RH signal line Ignition switch ON, load is applied to front occupant detection sensor RH Pulse generation
    Y1-9 (SIG3) - Y1-3 (SGD3) G - L Rear occupant detection sensor LH signal line Ignition switch ON, load is applied to rear occupant detection sensor LH Pulse generation
    Y1-10 (SIG4) - Y1-4 (SGD4) V - W Rear occupant detection sensor RH signal line Ignition switch ON, load is applied to rear occupant detection sensor RH Pulse generation
    HINT:
    *1: for Power Seat
    *2: for Manual Seat

    If the result is not as specified, the ECU may have a malfunction.

    Fig 1: Identifying Occupant Classification ECU Terminals
    G05155892Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002