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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 connectors.

    Fig 1: Measuring Voltage Between Terminals +B & E1 Of ECM Connectors
    G01496505Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: 

    Voltage: 9 to 14 V 

    1. OK: Proceed to next circuit inspection shown on 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 terminals IGSW of the ECM connector and the body ground.

    Fig 2: Measuring Voltage Between Terminals IGSW Of ECM Connector & Body Ground
    G01496506Courtesy 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: Checking Continuity Of IGN Fuse
    G01496507Courtesy 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  INSPECTION  ). 
    1. NG: Replace ignition switch. 
    2. OK: 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 terminals MREL of the ECM connector and the body ground.

    Fig 4: Measuring Voltage Between Terminals MREL Of ECM Connector & Body Ground
    G01496508Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: 

    Voltage: 9 to 14 V 

    1. NG: Replace ECM (See  HOW TO USE THE DIAGNOSTIC CHART AND INSPECTION PROCEDURE  ). 
    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  EFI MAIN RELAY  ). 
    1. NG: Replace EFI main relay. 
    2. OK: Go to next step. 
  9. Check for open and short in harness and connector between terminal EREL of ECM and body ground (See  HOW TO USE THE DIAGNOSTIC CHART AND INSPECTION PROCEDURE  ). 
    1. NG: Repair and replace harness or connector. 
    2. OK: Check and repair harness or connector between EFI fuse and battery.