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Inspection Procedure

WARNING: This page is about a different car, the 2008 Lexus IS F. However, it is still accessible from the selected car via links, so may be relevant.

HINT

If "+B of GND short malfunction of communication bus" DTCs (B1214 and B1215) are detected at the same time as "communication stop" DTC B1206, repair the "+B or GND short malfunction of communication bus" DTCs first (See DTC B1214 SHORT TO B+ IN DOOR SYSTEM COMMUNICATION BUS MALFUNCTION; DTC B1215 SHORT TO GND IN DOOR SYSTEM COMMUNICATION BUS MALFUNCTION  ).

  1. INSPECT FUSE (FR DOOR LH) 
    1. Remove the FR DOOR LH fuse from the main body ECU LH (cowl side junction block LH)
    2. Measure the resistance according to the value(s) in the table below

      Standard Resistance 

      RESISTANCE REFERENCE

      Tester Connection Condition Specified Condition
      FR DOOR LH fuse Always Below 1 Ω

    NG: REPLACE FUSE (FR DOOR LH) 

    OK: Go to Next Step 

  2. CHECK HARNESS AND CONNECTOR (MULTIPLEX NETWORK MASTER SWITCH BATTERY AND BODY GROUND) 
    1. Disconnect the M7 connector.
    2. Turn the engine switch on (IG).
    3. Measure the voltage and resistance according to the value(s) in the table below.

      Standard Voltage 

      VOLTAGE SPECIFICATION

      Tester Connection Condition Specified Condition
      M7-10 (BDR) - Body ground Always 11 to 14 V

      Standard Resistance 

      RESISTANCE REFERENCE

      Tester Connection Condition Specified Connection
      M7-2 (GND) - Body ground Always Below 1 Ω
    4. Fig 1: Identifying M7 Connector Terminal
      G05753992Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR (MULTIPLEX NETWORK MASTER SWITCH - BATTERY AND BODY GROUND) 

    OK: Go to Next Step 

  3. CHECK HARNESS AND CONNECTOR (COMMUNICATION LINE) 
    1. Disconnect the M7, Q3 and P33 connectors
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance 

      RESISTANCE REFERENCE

      Tester Connection Condition Specified Condition
      M7-7 (MPX1) - Q3-15 (MPX1) Always Below 1 Ω
      M7-8 (MPX2) - P33-28 (MPX2) Always Below 1 Ω
    3. Fig 2: Identifying M7, Q3 And P33 Connector Terminal
      G05753993Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: REPLACE MULTIPLEX NETWORK MASTER SWITCH  (See POWER WINDOW MASTER SWITCH )