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Inspection Procedure

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

    PREPARATION: 

    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
    G02921578Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: 

    Voltage: 9 to 14 V 

    1. OK: Proceed to next circuit inspection shown in the Problem symptoms table (See  BODY ELECTRICAL  ). 
    2. NG: Go to next step. 
  2. Check for open in harness and connector between terminal E1 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. 
  3. Check voltage between terminal IGSW of ECM connector and body ground. 

    PREPARATION: 

    Turn the ignition switch ON.

    CHECK: 

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

    Fig 2: Measuring Voltage Between Terminal IGSW
    G02921579Courtesy 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 IGN1 fuse. 

    PREPARATION: 

    Remove the IGN1 fuse from the instrument panel J/B.

    CHECK: 

    Check the continuity of the IGN1 fuse.

    Fig 3: Checking Continuity Of IGN1 Fuse
    G02921580Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: 

    Continuity 

    1. NG: Check for short in all harness and components connected to IGN1 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: 

    Turn the ignition switch ON.

    CHECK: 

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

    Fig 4: Measuring Voltage Between Terminal MREL
    G02921581Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: 

    Voltage: 9 to 14 V 

    1. NG: Replace ECM (See  INSPECTION  ). 
    2. OK: Go to next step. 
  7. Check EFI No. 1 fuse of engine room J/B. 

    PREPARATION: 

    Remove the EFI No. 1 fuse from the engine room J/B.

    CHECK: 

    Check continuity of EFI No. 1 fuse.

    Fig 5: Checking Continuity Of EFI No. 1 Fuse
    G02921582Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: 

    Continuity 

    1. NG: Check for short in all harness and components connected to EFI No. 1 fuse. 
    2. OK: Go to next step. 
  8. Check EFI relay (See  EFI MAIN RELAY  ). 
    1. NG: Replace EFI 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: Check and repair harness or connector between EFI No. 1 fuse and battery. 
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