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Inspection Procedure

  1. Check voltage between terminals + B and E1 of ECM connector. 

    PREPARATION: 

    1. Remove the ECM hood (See ENGINE CONTROL MODULE (ECM) ).
    2. Turn the ignition switch ON.

    CHECK: 

    Measure the voltage between terminals +B and E1 of the ECM connector.

    OK: 

    Voltage: 9 to 14 V 

    Fig 1: Measuring Voltage Between Terminals +B & E1 Of ECM Connector
    G01488205Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. OK: Proceed to next circuit inspection shown in the problem symptoms table (See  PROBLEM SYMPTOMS TABLE  ).  
    2. NG: Go to next step. 
  2. Check for open in harness and connector between terminal E1 of ECM connector and body ground (See  HOW TO USE THE DIAGNOSTIC CHART AND INSPECTION PROCEDURE  ).  
    1. NG: Repair or replace harness or connector. 
    2. OK: Go to next step. 
  3. Check voltage between terminal IGSW of ECM connector and body ground. 

    PREPARATION: 

    1. Remove the ECM hood (See ENGINE CONTROL MODULE (ECM) ).
    2. Turn the ignition switch ON.

    CHECK: 

    Measure the voltage between terminal IGSW of the ECM connector and the body ground.

    Fig 2: Measuring Voltage Between IGSW Terminal Of ECM Connector & Body Ground
    G01488206Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: 

    Voltage: 9 to 14 V 

    1. OK: Go to step   6 . 
    2. NG: Go to next step. 
  4. Check IGN fuse. 

    PREPARATION: 

    Remove the IGN fuse from the passenger side J/B.

    CHECK: 

    Check the continuity of the IGN fuse.

    Fig 3: Identifying IGN Fuse
    G01488207Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: 

    Continuity 

    1. NG: Check for short in all harness and components connected to IGN fuse. 
    2. OK: Go to next step. 
  5. Check ignition switch (See  PROBLEM SYMPTOMS TABLE  ).  
    1. NG: Replace ignition switch. 
    2. OK: Go to next step. 

      Check and repair harness and connector between battery and ignition switch, and ignition switch and ECM. 

  6. Check voltage between terminal MREL of ECM connector and body ground. 

    PREPARATION: 

    1. Remove the ECM hood (See ENGINE CONTROL MODULE (ECM) ).
    2. Turn the ignition switch ON.

    CHECK: 

    Measure the voltage between terminal MREL of the ECM connector and the body ground.

    Fig 4: Measuring Voltage Between MREL Terminal Of ECM Connector & Body Ground
    G01488208Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: 

    Voltage: 9 to 14 V 

    1. NG: Replace ECM (See  ENGINE CONTROL MODULE (ECM)  ).  
    2. OK: Go to next step. 
  7. Check EFI fuse. 
    1. NG: Check for short in all harness and components connected to EFI fuse. 
    2. OK: Go to next step. 
  8. Check EFI main relay (Marking: EFI) (See  INSPECTION  ).  
    1. NG: Replace EFI main relay. 
    2. OK: Go to next step. 
  9. Check for open and short in harness and connector between terminal MREL of ECM and body ground (See  HOW TO USE THE DIAGNOSTIC CHART AND INSPECTION PROCEDURE  ).  
    1. NG: Repair or replace harness or connector. 
    2. OK: Go to next step. 

      Check and repair harness or connector between EFI fuse and battery. 

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