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Inspection Procedure

WARNING: This page is about a different car, the 2002 Toyota Prius. However, it is still accessible from the selected car via links, so may be relevant.
  1. Check ECU-B and ECU-IG fuse. 

    CHECK:  continuity of ECU-B and ECU-IG fuse.

    OK:  Continuity.

    1. NG:  Replace the failure fuse.
    2. OK: Go to   2 . 
  2. Check voltage between terminals BATT, IG and GND of body ECU connector. 

    PREPARATION

    1. Turn ignition switch OFF.
    2. Disconnect the gateway ECU connector.

    CHECK:  Measure voltage between terminals BATT and GND.

    OK:  Voltage: 10 - 14 V.

    1. OK:  Check and repair wire harness and connector between gateway ECU and battery.
    2. NG:  Go to  3.
  3. Check wire harness and connector between gateway ECU and body ground  . See HOW TO USE THE DIAGNOSTIC CHART AND INSPECTION PROCEDURE .
    1. NG:  Repair or replace wire harness or connector.
    2. OK:  Check and repair wire harness and connector between gateway ECU and battery.