LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Toyota >> 2009 >> Avalon XLS >> Repair and Diagnosis >> Engine Performance >> Engine Control System (2GR-FE) >> SFI System >> Circuit Test >> ECM Power Source Circuit >> Inspection Procedure
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Inspection Procedure

  1. CHECK HARNESS AND CONNECTOR (ECM - BODY GROUND) 
    1. Disconnect the ECM connector.
    2. Measure the resistance between the terminals.

      Standard resistance 

      RESISTANCE SPECIFIED CONDITIONS

      Tester Connection Specified Condition
      E1 (B50-81) - Body ground Below 1 Ω
    3. Reconnect the ECM connector.

      NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

      Fig 1: Identifying Terminal E1 Of B50 ECM Connector
      G05404741Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      OK: Go to next step 

  2. CHECK ENGINE ROOM JUNCTION BLOCK (EFI RELAY VOLTAGE) 
    1. Remove the EFI No. 1 fuse from the engine room R/B.
    2. Turn the ignition switch to ON.
    3. Measure the voltage between the terminals.

      Standard voltage 

      VOLTAGE SPECIFIED CONDITION

      Tester Connection Specified Condition
      EFI No. 1 fuse (1) - Body ground 9 to 14 V

      NG: REPAIR OR REPLACE HARNESS OR CONNECTOR (EFI NO. 1 FUSE - BATTERY) 

      Fig 2: Identifying EFI No. 1 Fuse On Engine Room R/B
      G06227197Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      OK: Go to next step 

  3. INSPECT EFI NO. 1 FUSE 
    1. Remove the EFI No. 1 fuse from the engine room R/B.
    2. Measure the EFI No. 1 fuse resistance.

      Standard resistance: 

      Below 1 Ω 

    3. Reinstall the EFI No. 1 fuse.

      NG: REPLACE EFI NO. 1 FUSE 

      Fig 3: Identifying EFI No. 1 Fuse On Engine Room R/B
      G04996501Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      OK: Go to next step 

  4. INSPECT ENGINE ROOM JUNCTION BLOCK (EFI RELAY) 
    1. Remove the engine room junction block from the engine room R/B.
    2. Measure the resistance between the terminals.

      Standard resistance 

      RESISTANCE SPECIFIED CONDITIONS

      Tester Connection Specified Condition
      1D-4 - 1D-6 10 kΩ or higher
      1D-4 - 1D-6 Below 1 Ω (Battery voltage applied between terminals 1H-10 and 1H-2)
    3. Reinstall the engine room junction block.

      NG: REPLACE ENGINE ROOM JUNCTION BLOCK 

      Fig 4: Identifying Engine Room Junction Block Assembly
      G05404744Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      OK: Go to next step 

  5. CHECK HARNESS AND CONNECTOR (ECM - ENGINE ROOM JUNCTION BLOCK) 
    1. Disconnect the ECM connector.
    2. Remove the engine room junction block from the engine room R/B.
    3. Measure the resistance between the terminals.

      Standard resistance (Check for open) 

      RESISTANCE SPECIFIED CONDITIONS

      Tester Connection Specified Condition
      1D-4 - +B (A55-2) Below 1 Ω
      1D-4 - +B2 (A55-1) Below 1 Ω

      Standard resistance (Check for short) 

      RESISTANCE SPECIFIED CONDITIONS

      Tester Connection Specified Condition
      1D-4 or +B (A55-2) - Body ground 10 kΩ or higher
      1D-4 or +B2 (A55-1) - Body ground 10 kΩ or higher
    4. Reinstall the engine room junction block.
    5. Reconnect the ECM connector.

      NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

      Fig 5: Identifying Engine Room Junction Block And ECM Connector
      G05404745Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      OK: Go to next step 

  6. INSPECT ECM (IGSW VOLTAGE) 
    1. Disconnect the ECM connector.
    2. Measure the voltage between the terminals.

      Standard voltage 

      VOLTAGE SPECIFIED CONDITION

      Tester Connection Specified Condition
      IGSW (A55-28) - Body ground 9 to 14 V
    3. Reconnect the ECM connector.

      OK: Go to step  10

      Fig 6: Identifying Terminal IGSW Of A55 ECM Connector
      G04973803Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      NG: Go to next step 

  7. INSPECT RELAY (IG2 RELAY) 
    1. Remove the IG2 relay from the engine room R/B.
    2. Measure the resistance the terminals.

      Standard resistance 

      RESISTANCE SPECIFIED CONDITIONS

      Tester Connection Specified Condition
      3-5 10 kΩ or higher
      3-5 Below 1 Ω (Battery voltage applied between terminals 1 and 2)
    3. Reinstall the IG2 relay.

      NG: REPLACE RELAY (IG2 RELAY) 

      Fig 7: IG2 Relay Circuit
      G04942976Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      OK: Go to next step 

  8. CHECK HARNESS AND CONNECTOR (IG2 RELAY - BODY GROUND) 
    1. Remove the IG2 relay from the engine room R/B.
    2. Measure the resistance between the terminals.

      Standard resistance 

      RESISTANCE SPECIFIED CONDITIONS

      Tester Connection Specified Condition
      IG2 relay terminal 2 - Body ground Below 1 Ω
      Fig 8: Identifying IG2 Relay On Engine Room R/B
      G05404748Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    3. Reinstall the IG2 relay.

      Result 

      RESULT CHART

      Result Proceed to
      OK (w/o Smart key system) A
      OK (w/ Smart key system) B
      NG C

      B: GO TO SMART KEY SYSTEM  (See HOW TO PROCEED WITH TROUBLESHOOTING )

      C: REPAIR OR REPLACE HARNESS OR CONNECTOR 

      A: Go to next step 

  9. INSPECT IGNITION SWITCH ASSEMBLY 
    1. Disconnect the ignition switch connector.
    2. Measure the resistance between the terminals.

      Standard resistance 

      RESISTANCE SPECIFIED CONDITIONS

      Tester Connection Ignition Switch Position Specified Condition
      All terminals LOCK 10 kΩ or higher
      2 - 4 ACC Below 1 Ω
      1 - 2 - 4, 5 - 6 ON
      1 - 3 - 4, 5- 6 - 7 START
    3. Reconnect the ignition switch connector.
      Fig 9: Identifying Ignition Switch Connector Terminals
      G04973181Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      NG: REPLACE IGNITION SWITCH ASSEMBLY 

      OK: REPAIR OR REPLACE HARNESS OR CONNECTOR (ECM - BATTERY) 

  10. CHECK HARNESS AND CONNECTOR (ECM - EFI RELAY) 
    1. Disconnect the ECM connector.
    2. Remove the engine room junction block.
    3. Measure the resistance between the terminals.

      Standard resistance 

      RESISTANCE SPECIFIED CONDITIONS

      Tester Connection Specified Condition
      MREL (A55-44) - 1H-10 Below 1 Ω
    4. Reconnect the ECM connector.

      NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

      Fig 10: Identifying Engine Room Junction Block And ECM Connector
      G05404750Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      OK: REPLACE ECM (See  REMOVAL   ) 

scientia non olet · About LEMON Manuals