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Inspection Procedure

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

    PREPARATION: 

    Turn the ignition switch ON.

    CHECK: 

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

    OK: 

    1. Voltage: 9 to 14 V 
    Fig 1: Locating E1 and +B terminal of E7 and E9 ECM Connectors
    G02910443Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    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 and body ground (See  HOW TO TROUBLESHOOT ECU CONTROLLED SYSTEMS  ). 
    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.

    OK: 

    1. Voltage: 9 to 14 V 
    Fig 2: Locating IGSW Terminal of E9 ECM Connector
    G02910444Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. OK: Go to step   6 . 
    2. NG: Go to Next Step 
  4. Check IGN fuse. 

    PREPARATION: 

    Remove the IGN fuse from the cowl side J/B RH.

    CHECK: 

    Check the continuity of the IGN fuse.

    OK: 

    1. Continuity 
    Fig 3: Removing IGN Fuse from Cowl side J/B RH
    G02910445Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    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  IGNITION SWITCH & KEY UNLOCK WARNING SWITCH  ). 
    1. NG: Replace ignition switch. 
    2. OK: Check and repair harness and connector between battery and ignition switch, and ignition switch and ECM (See  HOW TO TROUBLESHOOT ECU CONTROLLED SYSTEMS  ). 
  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.

    OK: 

    1. Voltage: 9 to 14 V 
    Fig 4: Locating MREL Terminal of E9 ECM Connector
    G02910446Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. NG: Replace ECM (See  INSPECTION  ). 
    2. OK: Go to Next Step 
  7. Check EFI or ECD No. 1 fuse of engine room J/B. 

    PREPARATION: 

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

    CHECK: 

    Check continuity of EFI or ECD No. 1 fuse.

    OK: 

    1. Continuity 
    Fig 5: Removing EFI or ECD No. 1 Fuse from engine room J/B
    G02910447Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. NG: Check for short in all harness and components connected to EFI or ECD No. 1 fuse. 
    2. OK: Go to Next Step 
  8. Check EFI or ECD relay (See removal under  EFI MAIN RELAY  ). 
    1. NG: Replace EFI or ECD 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 TROUBLESHOOT ECU CONTROLLED SYSTEMS  ). 
    1. NG: Repair or replace harness or connector. 
    2. OK: Check and repair harness or connector between EFI or ECD No. 1 fuse and battery (See  HOW TO TROUBLESHOOT ECU CONTROLLED SYSTEMS  ). 
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