LIGHTING SYSTEM TERMINALS OF ECU


  1. CHECK INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY AND MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU)

    A005DU3E02
    Text in Illustration
    *A Main Body ECU (Multiplex Network Body ECU) with 3 connectors *B for LHD
    *C for RHD - -
    *1 Main Body ECU (Multiplex Network Body ECU) *2 3 connectors
    A005C58E02
    Text in Illustration
    *A Main Body ECU (Multiplex Network Body ECU) with 1 connectors *B for LHD
    *C for RHD - -
    *1 Main Body ECU (Multiplex Network Body ECU) *2 1 connector

    1. Disconnect the 2A, 2B, 2C, 2E, 2F and L8 instrument panel junction block assembly and main body ECU (multiplex network body ECU) connectors.

    2. Measure the voltage according to the value(s) in the table below.

      Terminal No. (Symbol) Wiring Color Terminal Description Condition Specified Condition
      2A-43 - Body ground G - Body ground ACC power supply Power switch on (ACC) 11 to 14 V
      Power switch off Below 1 V
      2B-25 - Body ground B - Body ground IG power supply Power switch on (IG) 11 to 14 V
      Power switch off Below 1 V
      2C-18 (BECU) - Body ground Y - Body ground Auxiliary battery power supply Power switch off 11 to 14 V
      2E-1*1 - Body ground W - Body ground Auxiliary battery power supply Power switch off 11 to 14 V
      2F-1*2 - Body ground W - Body ground Auxiliary battery power supply Power switch off 11 to 14 V

      If the result is not as specified, there may be a malfunction in the wire harness.

    3. Measure the resistance according to the value(s) in the table below.

      Terminal No. (Symbol) Wiring Color Terminal Description Condition Specified Condition
      2B-6 (GND1) - Body ground W-B - Body ground Ground Always Below 1 Ω
      L8-3 (GND2)*5 - Body ground W-B - Body ground Ground Always Below 1 Ω

      If the result is not as specified, there may be a malfunction in the wire harness.

    4. Reconnect the 2A, 2B, 2C, 2E, 2F and L8 instrument panel junction block assembly and main body ECU (multiplex network body ECU) connectors.

    5. Measure the voltage or check for pulses according to the value(s) in the table below.

      Terminal No. (Symbol) Wiring Color Terminal Description Condition Specified Condition
      2B-26 (RFGO) - Body ground Y - Body ground Rear fog light drive output Light control switch in tail position, rear fog light switch on Below 1 V
      Light control switch in tail position, rear fog light switch off 11 to 14 V
      2C-8*3 - Body ground LG - Body ground Front fog lights drive output Light control switch in tail position, front fog light switch on 11 to 14 V
      Light control switch in tail position, front fog light switch off Below 1 V
      2C-20 (PKB) - Body ground R - Body ground Parking brake switch input Parking brake switch on Below 1 V
      Parking brake switch off 11 to 14 V
      2C-22 (DIM) - Body ground Y - Body ground High beam headlights drive output Dimmer switch in high or high flash position Below 1 V
      Dimmer switch in low position 11 to 14 V
      2C-32 (HRLY) - Body ground G - Body ground Headlight relay drive output Light control switch in head position Below 1 V
      Light control switch not in head position 11 to 14 V
      L7-1 (RFOG) - Body ground W - Body ground Rear fog light switch input Rear fog light switch on Below 1 V
      Rear fog light switch off Pulse generation
      L7-8 (HF) - Body ground R - Body ground Dimmer switch high flash position signal input Dimmer switch in high flash position Below 1 V
      Dimmer switch not in high flash position Pulse generation
      L7-15 (DRLE) - Body ground Y - Body ground Daytime running light system drive output Daytime running light system operating Below 1 V
      Daytime running light system not operating 11 to 14 V
      L7-20 (CLTB) - L7-22 (CLTE)*4 R - B Automatic light control sensor power supply output Power switch off Below 1 V
      Power switch on (IG) and light control switch in AUTO position 11 to 14 V
      L7-21 (CLTS) - Body ground W - Body ground Automatic light control sensor signal input Power switch off Below 1 V
      Automatic light control system operates

      Pulse generation

      (See waveform 1)
      L7-27 (FFOG)*3 - Body ground SB - Body ground Front fog light switch input Front fog light switch on Below 1 V
      Front fog light switch off Pulse generation
      L7-28 (A)*4 - Body ground G - Body ground Light control switch AUTO position signal input Light control switch in AUTO position Below 1 V
      Light control switch not in AUTO position Pulse generation
      L7-29 (HEAD) - Body ground P - Body ground Light control switch head position input Light control switch in head position Below 1 V
      Light control switch not in head position Pulse generation
      L7-30 (TAIL) - Body ground Y - Body ground Light control switch tail position signal input Light control switch in tail or head position Below 1 V
      Light control switch in neither tail nor head position 11 to 14 V
      L8-5 (RLEW)*6 - Body ground L - Body ground Light control ECU RH signal input Power switch on (IG) and light control switch off 11 to 14 V
      Power switch on (IG) and light control switch in head position Pulse generation
      L8-21 (LLEW)*6 - Body ground B - Body ground Light control ECU LH signal input Power switch on (IG) and light control switch off 11 to 14 V
      Power switch on (IG) and light control switch in head position Pulse generation
      L8-17 (AHBI)*7 - Body ground R - Body ground Auto high beam switch signal input Auto high beam switch on Below 1 V
      Auto high beam switch off 11 to 14 V

      If the result is not as specified, the main body ECU (multiplex network body ECU) or instrument panel junction block assembly may have a malfunction.


      • *1: for LHD

      • *2: for RHD

      • *3: w/ Front Fog Light

      • *4: w/ Automatic Light Control

      • *5: Main Body ECU (Multiplex Network Body ECU) with 3 connectors

      • *6: for LED Headlight

      • *7: w/ Automatic High Beam System


      1. A005CZME30

        Waveform 1

        Item Content
        Tool setting 5 V/DIV., 5 ms./DIV.

        Tech Tips

        If the ambient light becomes brighter, width A becomes narrower.

  2. CHECK HEADLIGHT LEVELING ECU ASSEMBLY

    A005CEIE03

    1. Disconnect the A48 headlight leveling ECU assembly connector.

    2. Measure the voltage and resistance according to the value(s) in the table below.

      Standard Voltage
      Terminal No. (Symbol) Wiring Color Terminal Description Condition Specified Condition
      A48-1 (IG) - Body ground LG - Body ground IG power supply Power switch off Below 1 V
      Power switch on (IG) 11 to 14 V
      Standard Resistance
      Terminal No. (Symbol) Wiring Color Terminal Description Condition Specified Condition
      A48-9 (E1) - Body ground W-B - Body ground Ground Always Below 1 Ω

      If the result is not as specified, there may be a malfunction on the wire harness side.

    3. Reconnect the A48 headlight leveling ECU assembly connector.

    4. Measure the resistance and voltage according to the value(s) in the table below.

      Standard Resistance
      Terminal No. (Symbol) Wiring Color Terminal Description Condition Specified Condition
      A48-21 (SGR) - Body ground Y - Body ground Rear height control sensor ground Always Below 1 Ω
      A48-23 (RH-) - Body ground BR - Body ground Leveling motor RH ground Always Below 1 Ω
      A48-24 (LH-) - Body ground LG - Body ground Leveling motor LH ground Always Below 1 Ω
      Standard Voltage
      Terminal No. (Symbol) Wiring Color Terminal Description Condition Specified Condition
      A48-3 (HDLP) - Body ground V - Body ground Low beam headlight signal input Low beam headlights on Below 1.5 V
      Low beam headlights off Above 5 V
      A48-5 (INIT) - Body ground B - Body ground Initialization signal input Terminals LVL and GND of DLC3 connected Below 1 V
      Terminals LVL and GND of DLC3 not connected Approximately 5 V
      A48-6 (WNG) - Body ground L - Body ground Warning light drive output Warning light on Below 1 V
      Warning light off 11 to 14 V
      A48-10 (RH+) - Body ground W - Body ground Leveling motor RH power supply Power switch off Below 1 V
      Power switch on (IG) 11 to 14 V
      A48-11 (LH+) - Body ground R - Body ground Leveling motor LH power supply Power switch off Below 1 V
      Power switch on (IG) 11 to 14 V
      A48-12 (SBR) - Body ground P - Body ground Rear height control sensor power supply Power switch off Below 1 V
      Power switch on (IG) 4.75 to 5.25 V
      A48-16 (SPDR) - Body ground V - Body ground Vehicle speed signal input Vehicle is driven at approximately 20 km/h (12 mph)

      Pulse generation

      (See waveform 1)
      A48-17 (RHT) - Body ground B - Body ground Leveling motor RH operation signal input With low beam headlights on, vehicle height not changed Below 1 V
      With low beam headlights on, change vehicle height and keep for more than 3 seconds 1.0 to 14.4 V
      A48-18 (LHT) - Body ground G - Body ground Leveling motor LH operation signal input With low beam headlights on, vehicle height not changed Below 1 V
      With low beam headlights on, change vehicle height and keep for more than 3 seconds 1.0 to 14.4 V
      A48-19 (SHRL) - Body ground SB - Body ground Rear height control sensor signal input Power switch off Below 1 V
      Power switch on (IG) 0.5 to 4.5 V

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


      1. A0059T4

        Waveform 1

        Item Content
        Tool setting 2 V/DIV., 2 ms./DIV.

  3. CHECK POWER MANAGEMENT CONTROL ECU

    A005CO2E02

    1. Disconnect the A21 power management control ECU connector.

    2. Measure the voltage and resistance according to the value(s) in the table below.

      Standard Voltage
      Terminal No. (Symbol) Wiring Color Terminal Description Condition Specified Condition
      A21-15 (BL) - Body ground R - Body ground Back up light Power switch on (IG), shift lever in R 11 to 14 V

      If the result is not as specified, there may be a malfunction on the wire harness side.