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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 B1296, 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 (MPX-B) 
    1. Remove the MPX-B fuse from the engine room relay block No 1
    2. Measure the resistance according to the value(s) in the table below

      Standard Resistance 

      RESISTANCE REFERENCE

      Tester Connection Condition Specified Condition
      MPX-B fuse Always Below 1 Ω

    NG: REPLACE FUSE (MPX-B) 

    OK: Go to Next Step 

  2. CHECK HARNESS AND CONNECTOR (FRONT CONTROLLER (ENGINE ROOM RELAY BLOCK NO. 2)) - BATTERY AND BODY GROUND) 
    1. Disconnect the 2E and 2F connectors.
    2. Measure the voltage and resistance according to the value(s) in the table below.

      Standard Voltage 

      VOLTAGE SPECIFICATION

      Tester Connection Condition Specified Condition
      2E-4 (FMB3) - Body ground Always 11 to 14 V

      Standard Resistance 

      RESISTANCE REFERENCE

      Tester Connection Condition Specified Condition
      2F-1 (E) - Body ground Always Below 1 Ω
    3. Fig 1: Identifying 2E And 2F Connector Terminal
      G05754084Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR (FRONT CONTROLLER (ENGINE ROOM RELAY BLOCK NO. 2)) BATTERY AND BODY GROUND) 

    OK: Go to Next Step 

  3. CHECK HARNESS AND CONNECTOR (COMMUNICATION LINE) 
    1. Disconnect the 2F, A30 and J55 connectors.
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance 

      RESISTANCE REFERENCE

      Tester Connection Condition Specified Condition
      2F-6 (MPX2) - A30-17 (MPX2) Always Below 1 Ω
      2F-5 (MPX1) - J55-24 (MPX2) Always Below 1 Ω
    3. Fig 2: Identifying 2F, A30 And J55 Connector Terminal
      G05754085Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: REPLACE FRONT CONTROLLER (ENGINE ROOM RELAY BLOCK NO. 2)