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Inspection Procedure

HINT:

Read freeze frame data using the Techstream. Freeze frame data records the engine condition when malfunctions are detected. When troubleshooting, freeze frame data can help determine if the vehicle was moving or stationary, if the engine was warmed up or not, if the air-fuel ratio was lean or rich, and other data from the time the malfunction occurred.

  1. CHECK ECM (FRP VOLTAGE) 
    1. Measure the voltage according to the value(s) in the table below.

      Standard Voltage 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Condition Specified Condition
      A14-6 (FPR) - E3-1 (E1) STA signal ON 9 to 14 V
      A14-6 (FPR) - E3-1 (E1) STA signal OFF 0 to 3 V
      Fig 1: Identifying Terminals Of E3 And A14 ECM Connectors
      G04942764Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPLACE ECM  (See REMOVAL )

    OK: Go to Next Step 

  2. INSPECT FUEL PUMP RELAY (F/PMP) 
    1. Remove the F/PMP relay from the engine room No. 2 relay block.
    2. Measure the resistance according to the value(s) in the table below.

      Standard Resistance 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Condition Specified Condition
      3 - 4 When no battery applied to terminals 1 and 2 Below 1 Ω
      3 - 4 When battery voltage is applied to terminals 1 and 2 10 kΩ or more
      Fig 2: Identifying Terminals Of F/PMP Relay
      G04942765Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPLACE FUEL PUMP RELAY (F/PMP)  (See ON-VEHICLE INSPECTION )

    OK: Go to Next Step 

  3. CHECK HARNESS AND CONNECTOR (F/PMP RELAY - ECM) 
    1. Remove the F/PMP relay from the engine room No. 2 relay block.
    2. Disconnect the A14 ECM connector.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance (Check for open) 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Condition Specified Condition
      F/PMP relay (2) - A14-6 (FPR) Always Below 1 Ω

      Standard Resistance (Check for short) 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Condition Specified Condition
      F/PMP relay (2) or A14-6 (FPR) - Body Ground Always 10 kΩ or higher
      Fig 3: Identifying Terminals Of A14 ECM Connector
      G04942766Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: REPLACE ECM  (See REMOVAL )