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Light Failure Relay Circuit

WARNING: This page is about a different car, the 2003 Lexus RX 300 and 2002 Lexus RX 300. However, it is still accessible from the selected car via links, so may be relevant.
  1. Disconnect the connector from the relay and inspect the connector on the wiring harness side. See CONNECTOR IDENTIFICATION . See INSPECTING LIGHT FAILURE RELAY CIRCUIT  table.
    INSPECTING LIGHT FAILURE RELAY CIRCUIT

    Tester Connection Condition Specified Condition
    1 - Ground Constant Continuity (1)
    2 - Ground Constant Continuity (1)
    9 - Ground Constant Continuity (1)
    11 - Ground Constant Continuity
    3 - Ground Light Control Switch OFF No Voltage
    3 - Ground Light Control Switch TAIL Or HEAD B+ Voltage
    4 - Ground Ignition Switch LOCK Or ACC No Voltage
    4 - Ground Ignition Switch ON B+ Voltage
    7 - Ground Stop Light Switch OFF No Voltage
    7 - Ground Stop Light Switch ON B+ Voltage
    8 - Ground Ignition Switch LOCK Or ACC No Voltage
    8 - Ground Ignition Switch ON B+ Voltage
    (1) There is resistance because this circuit is grounded through the bulb.
  2. If the circuit is as specified, replace the relay. If the circuit is not as specified, inspect the circuits connected to other parts.