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Inspection Procedure

WARNING: This page is about a different car, the 2003 Lexus LS 430. However, it is still accessible from the selected car via links, so may be relevant.
  1. Check D SEAT and MPX-B1 fuse. 

    CHECK: 

    Check continuity of D SEAT and MPX-B1 fuse.

    OK: 

    Continuity 

    1. NG : Replace the failure fuse. 
    2. OK : Go to next step. 
  2. Check voltage between terminals SYSB, +B, IG and GND of power seat ECU connector. 

    PREPARATION: 

    Turn the ignition switch ON.

    CHECK: 

    Measure voltage between terminals IG and GND.

    OK: 

    Voltage: 10 - 14 V 

    PREPARATION: 

    1. Turn the ignition switch OFF
    2. Disconnect the driver seat ECU connector.

    CHECK: 

    Measure voltage between terminals SYSB, +B and GND.

    1. OK : Proceed to next circuit inspection shown on problem symptoms table (See  PROBLEM SYMPTOMS TABLE  ). 
    2. NG : Go to next step. 
  3. Check harness and connector between driver seat ECU and body ground (See  HOW TO USE THE DIAGNOSTIC CHART AND INSPECTION PROCEDURE  ). 
    1. OK : Repair or replace harness or connector. 
    2. NG : Proceed to next circuit inspection shown on problem symptom table (See  PROBLEM SYMPTOMS TABLE  ).