SFI SYSTEM ECM Power Source Circuit

DESCRIPTION

When the power switch is turned on (IG), auxiliary battery voltage is applied to the IGSW terminal of the ECM. The output signal from the MREL terminal of the ECM causes current to flow to the coil of the No. 1 integration relay (EFI MAIN relay), closing the contact and supplying power to terminals +B and +B2 of the ECM.

CAUTION / NOTICE / HINT

PROCEDURE

1. Click here

   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 D24-16 (E1) - Body ground Always Below 1 Ω

   
   
   • OKClick here
   • NG

     REPAIR OR REPLACE HARNESS OR CONNECTOR

2. Click here

   CHECK TERMINAL VOLTAGE (IGSW VOLTAGE)

   
   
   1. 

      Disconnect the ECM connector.

   2. Turn the power switch on (IG).

   3. Measure the voltage according to the value(s) in the table below.

      Standard Voltage
      Tester Connection Condition Specified Condition A22-37 (IGSW) - Body ground Power switch on (IG) 11 to 14 V

      Table 1. Text in Illustration

      *a	Front view of wire harness connector (to ECM)

   
   
   • OKClick here
   • NGClick here
3. Click here

   INSPECT NO. 1 INTEGRATION RELAY (EFI MAIN RELAY)

   
   

   1. Inspect the No. 1 integration relay (EFI MAIN relay) (Click here).

   
   
   • OKClick here
   • NG

     REPLACE NO. 1 INTEGRATION RELAY (EFI MAIN RELAY) (Click here)

4. Click here

   CHECK HARNESS AND CONNECTOR (NO. 1 INTEGRATION RELAY - ECM)

   
   

   1. Remove the No. 1 integration relay from the engine room relay block and junction block assembly.

   2. Disconnect the ECM connector.

   3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition 1C-9 - A22-2 (+B) Always Below 1 Ω 1C-10 - A22-3 (+B2) Always Below 1 Ω 1C-7 - A22-46 (MREL) Always Below 1 Ω 1C-9 or A22-2 (+B) - Body ground Always 10 kΩ or higher 1C-10 or A22-3 (+B2) - Body ground Always 10 kΩ or higher 1C-7 or A22-46 (MREL) - Body ground Always 10 kΩ or higher

   
   
   • OKClick here
   • NG

     REPAIR OR REPLACE HARNESS OR CONNECTOR

5. Click here

   CHECK TERMINAL VOLTAGE (POWER SOURCE OF NO. 1 INTEGRATION RELAY)

   
   
   1. 

      Remove the No. 1 integration relay from the engine room relay block and junction block assembly.

   2. Measure the voltage according to the value(s) in the table below.

      Standard Voltage
      Tester Connection Condition Specified Condition 1B-1 - Body ground Always 11 to 14 V

      Table 2. Text in Illustration

      *a	Front view of wire harness connector (to No. 1 Integration Relay)

   
   
   • OK

     PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE (Click here)

   • NG

     REPAIR OR REPLACE HARNESS OR CONNECTOR (AUXILIARY BATTERY - NO. 1 INTEGRATION RELAY)

6. Click here

   INSPECT NO. 1 INTEGRATION RELAY (IG2 RELAY)

   
   

   1. Inspect the No. 1 integration relay (IG2 relay) (Click here).

   
   
   • OKClick here
   • NG

     REPLACE NO. 1 INTEGRATION RELAY (IG2 RELAY) (Click here)

7. Click here

   CHECK HARNESS AND CONNECTOR (NO. 1 INTEGRATION RELAY - ECM)

   
   

   1. Remove the No. 1 integration relay from the engine room relay block and junction block assembly.

   2. Disconnect the ECM connector.

   3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition 1C-1 - A22-37 (IGSW) Always Below 1 Ω 1C-1 or A22-37 (IGSW) - Body ground Always 10 kΩ or higher

   
   
   • OKClick here
   • NG

     REPAIR OR REPLACE HARNESS OR CONNECTOR

8. Click here

   CHECK TERMINAL VOLTAGE (POWER SOURCE OF NO. 1 INTEGRATION RELAY)

   
   
   1. 

      Remove the No. 1 integration relay from the engine room relay block and junction block assembly.

   2. Measure the voltage according to the value(s) in the table below.

      Standard Voltage
      Tester Connection Condition Specified Condition 1D-3 - Body ground Always 11 to 14 V

      Table 3. Text in Illustration

      *a	Front view of wire harness connector (to No. 1 Integration Relay)

   
   
   • OKClick here
   • NG

     REPAIR OR REPLACE HARNESS OR CONNECTOR (AUXILIARY BATTERY - NO. 1 INTEGRATION RELAY)

9. Click here

   CHECK HARNESS AND CONNECTOR (NO. 1 INTEGRATION RELAY - BODY GROUND)

   
   

   1. Remove the No. 1 integration relay from the engine room relay block and junction block assembly.

   2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition 1E-2 - Body ground Always Below 1 Ω

   
   
   • OKClick here
   • NG

     REPAIR OR REPLACE HARNESS OR CONNECTOR

10. Click here

    CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU - NO. 1 INTEGRATION RELAY)

    
    

    1. Disconnect the certification ECU (smart key ECU assembly) connector.

    2. Remove the No. 1 integration relay from the engine room relay block and junction block assembly.

    3. Measure the resistance according to the value(s) in the table below.

       Standard Resistance
       Tester Connection Condition Specified Condition A72-9 (IG2D) - 1C-8 Always Below 1 Ω A72-9 (IG2D) or 1C-8 - Body ground Always 10 kΩ or higher

    
    
    • OK

      GO TO SMART ENTRY AND START SYSTEM (Click here)

    • NG

      REPAIR OR REPLACE HARNESS OR CONNECTOR