2018 Toyota 86 GT, Standard TransFACTORY OEM SERVICE PROCEDURE

ECM Power Source Circuit [06/2016 - 03/2017]: Procedure

  1. INSPECT ECM (POWER SOURCE VOLTAGE) 
    GTY730725Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Turn the ignition switch to ON.
    2. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Switch Condition Specified Condition
      A34-6 (+B) - A36-4 (E01) Ignition switch ON 12 to 14 V
      A33-1 (+B2) - A36-4 (E01) Ignition switch ON 12 to 14 V
      TEXT IN ILLUSTRATION

      *a Component with harness connected
      (ECM)

    Result: 

    NG 

    See step  4

    Result: 

    OK 

    See step  2

  2. CHECK HARNESS AND CONNECTOR (ECM - BODY GROUND) 
    1. Disconnect the ECM connector.
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      A36-4 (E01) - Body ground Always Below 1 Ω

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  3

  3. INSPECT ECM (IGSW TERMINAL VOLTAGE) 
    GTY708855Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Turn the ignition switch to ON.
    2. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Switch Condition Specified Condition
      A33-27 (IGSW) - A36-4 (E01) Ignition switch ON 10 to 13 V
      TEXT IN ILLUSTRATION

      *a Component without harness connected
      (ECM)

    Result: 

    OK 

    REPLACE ECM 

    (Refer to REMOVAL [06/2016 - ] )

    Result: 

    NG 

    See step  8

  4. INSPECT ECM (SSHUT TERMINAL VOLTAGE) 
    GTY713942Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Turn the ignition switch to ON.
    2. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Switch Condition Specified Condition
      A35-13 (SSHUT) - A36-4 (E01) Ignition switch ON approximately 0 V
      TEXT IN ILLUSTRATION

      *a Component without harness connected
      (ECM)

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  5

  5. INSPECT RELAY (EFI MAIN1) 
    1. Inspect the EFI MAIN1 relay (Refer to PROCEDURE - Step 1 ).

    Result: 

    NG 

    REPLACE RELAY (EFI MAIN1) 

    Result: 

    OK 

    See step  6

  6. CHECK HARNESS AND CONNECTOR (EFI MAIN1 RELAY - ECM) 
    1. Remove the EFI MAIN1 relay from the engine room relay block assembly.
    2. Disconnect the ECM connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance (Check for open)

      Tester Connection Condition Specified Condition
      EFI MAIN1 relay terminal 1 - A35-13 (SSHUT) Always Below 1 Ω
      EFI MAIN1 relay terminal 3 - A34-6 (+B) Always Below 1 Ω
      EFI MAIN1 relay terminal 3 - A33-1 (+B2) Always Below 1 Ω

      Standard Resistance (Check for short)

      Tester Connection Condition Specified Condition
      EFI MAIN1 relay terminal 1 or A35-13 (SSHUT) - Body ground Always 10 kΩ or higher
      EFI MAIN1 relay terminal 3, A34-6 (+B) or A33-1 (+B2) - Body ground Always 10 kΩ or higher

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  7

  7. INSPECT TERMINAL VOLTAGE (EFI MAIN1 RELAY) 
    1. Remove the EFI MAIN1 relay from the engine room relay block assembly.
      GTY471565Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      EFI MAIN1 relay terminal 2 - Body ground Always 11 to 14 V
      EFI MAIN1 relay terminal 5 - Body ground Always 11 to 14 V
      TEXT IN ILLUSTRATION

      *1 Engine Room Relay Block Assembly
      *2 EFI MAIN1 Relay Terminal

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  8

  8. CHECK HARNESS AND CONNECTOR (IG2 RELAY - ECM) 
    1. Remove the IG2 relay from the engine room relay block assembly.
    2. Disconnect the ECM connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance (Check for open)

      Tester Connection Condition Specified Condition
      IG2 relay terminal 3 - A33-27 (IGSW) Always Below 1 Ω
      IG2 relay terminal 1 - Body ground Always Below 1 Ω

      Standard Resistance (Check for short)

      Tester Connection Condition Specified Condition
      IG2 relay terminal 3 or A33-27 (IGSW) - Body ground Always 10 kΩ or higher

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  9

  9. INSPECT RELAY (IG2) 
    1. Inspect the IG2 relay (Refer to PROCEDURE - Step 4 ).

    Result: 

    NG 

    REPLACE RELAY (IG2) 

    Result: 

    OK 

    See step  10

  10. INSPECT TERMINAL VOLTAGE (IG2 RELAY) 
    1. Remove the IG2 relay from the engine room relay block assembly.
      GTY471753Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      IG2 relay terminal 5 - Body ground Always 11 to 14 V
      TEXT IN ILLUSTRATION

      *1 Engine Room Relay Block Assembly
      *2 IG2 Relay Terminal

    Result: 

    OK 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    NG 

    See step  11

  11. CHECK HARNESS AND CONNECTOR (IG2 RELAY - IGNITION OR STARTER SWITCH ASSEMBLY) 
    1. Remove the IG2 relay from the engine room relay block assembly.
    2. Disconnect the ignition or starter switch assembly connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance (Check for open)

      Tester Connection Condition Specified Condition
      IG2 relay terminal 2 - D55-6 (IG2) Always Below 1 Ω

      Standard Resistance (Check for short)

      Tester Connection Condition Specified Condition
      IG2 relay terminal 2 or D55-6 (IG2) - Body ground Always 10 kΩ or higher

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    OK 

    See step  12

  12. INSPECT IGNITION OR STARTER SWITCH ASSEMBLY 
    1. Inspect the ignition or starter switch assembly (Refer to INSPECTION [06/2016 - ] ).

    Result: 

    OK 

    REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Result: 

    NG 

    REPLACE IGNITION OR STARTER SWITCH ASSEMBLY 

    (Refer to REMOVAL [06/2016 - 03/2017] )

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Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • • You smell fuel, burning insulation, or see smoke.
  • • Brakes feel soft, pull hard to one side, or make grinding noises.
  • • The engine overheats, stalls repeatedly, or misfires under load.
  • • You are missing required tools, torque specs, or safe lifting equipment.
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