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4. Inspect Driver Side Junction Block Circuit

WARNING: This page is about a different car, the 2003 Lexus GS 430 and 2003 Lexus GS 300. However, it is still accessible from the selected car via links, so may be relevant.
Fig 1: Identifying Driver Side Junction Block Circuit
G03632561Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  1. Remove the fuse from the junction block and inspect the connector on junction block side.
    SPECIFIED CONDITION

    Fuse Tester connection Condition Specified condition
    AM1 1-Ground Constant Battery positive voltage
    WASHER 3-Ground Ignition switch ON Battery positive voltage
    FOG 5-Ground Constant Battery positive voltage
    TAIL 7-Ground Light control switch TAIL or HEAD Battery positive voltage
    GAUGE 11-Ground Ignition switch ON Battery positive voltage
    FUEL OPN 13-Ground Constant Battery positive voltage
    PANEL 17-Ground Light control switch TAIL or HEAD Battery positive voltage
    HEATER 19-Ground Ignition switch ON Battery positive voltage
    SRS-B 21-Ground Constant Battery positive voltage
    DP/SEAT 23-Ground Constant Battery positive voltage
    RADIO NO.2 25-Ground Ignition switch ACC or ON Battery positive voltage
    WIPER 27-Ground Ignition switch ON Battery positive voltage
    OBD 29-Ground Constant Battery positive voltage
    STOP 31-Ground Constant Battery positive voltage
    CIG 33-Ground Ignition switch ACC or ON Battery positive voltage
    ECU-IG 35-Ground Ignition switch ON Battery positive voltage
    ST 37-Ground Ignition switch ON Battery positive voltage
    IGN 39-Ground Ignition switch ON Battery positive voltage
    D RR DOOR 41-Ground Constant Battery positive voltage

    If the circuit is not as specified, inspect the circuits connected to other parts.

  2. Remove the relay from the junction block and inspect the connector on junction block side.
    SPECIFIED CONDITION

    Relay Tester connection Condition Specified condition
    Fog light 43-Ground Constant Battery positive voltage
    Fog light 44-Ground Constant Continuity
    Fog light 46-Ground Light control switch HEAD Battery positive voltage
    Taillight 47-Ground Constant Battery positive voltage
    Taillight 48-Ground Constant Continuity
    Taillight 50-Ground Constant Continuity

    If the circuit is not as specified, inspect the circuits connected to other parts.