LIGHTING SYSTEM Taillight Relay Circuit

DESCRIPTION

The main body ECU receives the light control switch tail signal to control the taillight relay. When the light control switch is in the AUTO position, the main body ECU receives the ambient light level signal from the automatic light control sensor to control the taillight relay.*


Tech Tips


  • When any of the lights do not illuminate, check the bulb or wire harness that is related to the light.

  • When none of the lights that are related to the tail relay illuminate and the TAIL fuse is normal, perform the taillight relay Active Test and read the light control switch tail signal value in the Data List to determine if the malfunction exists on either the switch side or the relay side.

  • The taillight relay is installed in the instrument panel junction block and cannot be removed for inspection.

WIRING DIAGRAM

A002QN7E03

CAUTION / NOTICE / HINT

Note

Inspect the fuses and bulbs for circuits related to this system before performing the following inspection procedure.

PROCEDURE


  1. PERFORM ACTIVE TEST USING INTELLIGENT TESTER (TAILLIGHT RELAY)


    1. Using the intelligent tester, perform the Active Test Click here.

      Main Body
      Tester Display Test Part Control Range Diagnostic Note
      Taillight Relay Taillight relay ON / OFF -
      OK
      Taillight relay operates (taillights illuminate).

    OK

    REPLACE MAIN BODY ECU (INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY)

    NG

  2. CHECK HARNESS AND CONNECTOR (BATTERY - MAIN BODY ECU)

    A002N27E02
    Text in Illustration
    *1

    Front view of wire harness connector

    (to Main Body ECU)

    1. Disconnect the DG main body ECU connector.

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

      Standard Voltage
      Tester Connection Condition Specified Condition
      DG-1 - Body ground Always 11 to 14 V

    OK

    PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE Click here

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR