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Inspection Procedure

HINT:

When "+B of GND short malfunction of communication bus" DTCs (B1214 and B1215) are detected at the same time as "communication stop" DTC B1279, repair the "+B or GND short malfunction of communication bus" DTCs first.

  1. INSPECT FUSE (ECU-IG LH) 
    1. Remove the ECU-IG LH fuse from the cowl side J/B LH.
    2. Measure the resistance of the fuse.

      Standard resistance: 

      Below 1 Ω 

    NG: REPLACE FUSE 

    OK: Go to next step 

  2. CHECK WIRE HARNESS (OVERHEAD J/B - BATTERY AND BODY GROUND) 
    1. Disconnect the R5 connector.
    2. Measure the voltage and resistance of the wire harness side connector.

    Standard voltage 

    TESTER CONNECTION SPECIFIED CONDITION REFERENCE CHART

    Tester Connection Condition Specified Condition
    IG (R5-21) - Body ground Engine switch on (IG) 10 to 14 V

    Standard resistance 

    TESTER CONNECTION SPECIFIED CONDITION REFERENCE CHART

    Tester Connection Specified Condition
    GND2 (R5-40) - Body ground Below 1 Ω
    Fig 1: Identifying R5 Connector Terminals
    G05828531Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  3. CHECK WIRE HARNESS (RAIN SENSOR - BATTERY AND BODY GROUND) 
    1. Disconnect the R7 connector.
    2. Measure the voltage and resistance of the wire harness side connector.

    Standard voltage 

    TESTER CONNECTION SPECIFIED CONDITION REFERENCE CHART

    Tester Connection Condition Specified Condition
    SIG (R7-1) - Body ground Engine switch on (IG) 10 to 14 V

    Standard resistance 

    TESTER CONNECTION SPECIFIED CONDITION REFERENCE CHART

    Tester Connection Specified Condition
    ES (R7-3) - Body ground Below 1 Ω
    Fig 2: Identifying R7 Connector Terminals
    G05275025Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

  4. CHECK RESISTANCE OF COMMUNICATION LINE 
    1. Disconnect the R7 and R5 ECU connectors.
    2. Measure the resistance between the specified terminals on the wire harness side connectors.

    Standard resistance 

TESTER CONNECTION SPECIFIED CONDITION REFERENCE CHART

Tester Connection Specified Condition
MPX (R7-2) - MPX1 (R5-37) Below 1 Ω

Result 

RESULT CHART

Result Proceed to
Both are OK A
One is OK B
Both are NG C
Fig 3: Identifying R7 And R5 ECU Connector Terminals
G05828533Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

B: REPAIR OR REPLACE HARNESS OR CONNECTOR OR REPLACE RAIN SENSOR 

C: REPAIR OR REPLACE HARNESS OR CONNECTOR 

A: REPLACE RAIN SENSOR 

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