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Inspection Procedure

HINT:

The diagnostic information output from the AID can be confirmed by connecting an oscilloscope to the diagnostic information terminal of the AID. It narrows the trouble area search to read the waveform on the oscilloscope when performing the AI system intrusive operation function provided in the SYSTEM CHECK.

  1. Start the engine and warm it up.
  2. Turn the ignition switch OFF.
  3. Connect the intelligent tester to the CAN VIM. Then connect the CAN VIM to the DLC3.
  4. Connect an oscilloscope probe to the AIDI terminal of the ECM.
    Fig 1: Identifying ECM Connector Terminals
    G04967925Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  5. Start the engine and turn the tester ON.
  6. On the tester, enter the following menus: DIAGNOSIS / ENHANCED OBD II / SYSTEM CHECK / AIR INJ SYSTEM.
  7. On the tester, enter the following menus: DIAGNOSIS / ENHANCED OBD II / SYSTEM CHECK / AIR INJ CHECK / MANUAL / OPERATION 1 and 2.
    Fig 2: Intelligent Tester Display - AIR INJ CHECK Menu
    G04968009Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    HINT:

    OPERATION 1: AP: OFF; EASV: CLOSE; ASV1: CLOSE; ASV2: CLOSE OPERATION 2: AP: ON; EASV: OPEN; ASV1: OPEN; ASV2: OPEN

  8. Monitor the voltage output of the AID (duty ratio signal).
    Fig 3: Voltage Output Of AID (Duty Ratio Signal)
    G04967927Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Oscilloscope range 

ITEMS CHART

Items Contents
Terminals CH1:AIDI-E1
Equipment Settings 5 V/Division, 20 to 40 ms/Division
Conditions Idling
NOTE:
  • This AIR INJECTION CHECK only allows technicians to operate the AI system for 5 seconds. Furthermore, the check can be performed 4 times a trip. If the test is repeated, intervals of at least 30 seconds are required between checks.

    While the AI system operation using the intelligent tester is prohibited, the tester displays the prohibition (Al STATUS NG) or ERROR. If ERROR (Al STATUS NG) is displayed on the tester, stop the engine for 10 minutes and then try again.

  • Performing the AIR INJ CHECK over and over again may cause damage in the secondary air injection system. If necessary, wait several minutes between tests to prevent overheating the system.
  • When performing the AIR INJ CHECK operation after the battery cable has been reconnected, wait for 7 minutes with the ignition switch turned ON or the engine running.
  • Turn the ignition switch OFF when the AIR INJ CHECK operation finishes.
SUSPECTED TROUBLE AREA CHART

AID Diagnostic Signal Waveform ECM Command DTC (ECM Output) Suspected Trouble Area
100% Duty Ratio See  1waveform 1 Any Air Injection (Al) System operation P1613 
  • Open in diagnostic signal circuit
  • Air Injection Control Driver (AID)
  • Open in AID +B circuit (AID power source)
  • Short between +B circuit and diagnostic signal circuit
0% Duty Ratio See  2waveform 2 AI System: ON (Air pump ON, ASV ON) P1613  Open or short in air pump or Air Switching Valve (ASV) command signal circuit (ECM - AID)
  • Open in AID ground circuit
  • Short between diagnostic signal circuit and body ground
  • AID
  • ECM
AI System: OFF (Air pump OFF, ASV OFF) - Normal
20% Duty Ratio See  3 waveform 3 Air Pump: ON P0418 
  • Short between air pump drive circuit and body ground
  • Harness & connector (AID - Pump) Air Pump
  • AID
  • ECM
Air Pump: OFF P0418 
  • Open in air pump drive circuit (AID - Pump), or short between air pump drive circuit and +B
  • Harness & connector (AID -Pump)
  • Air Pump
  • AID
  • ECM
40% Duty Ratio See  4waveform 4 ASV: ON P0412 
  • Short between ASV drive circuit and body ground Harness & connector (AID - ASV)
  • ASV
  • AID
  • ECM
ASV: OFF P0412 
  • Open in ASV drive circuit (AID - ASV), or short between ASV drive circuit and +B
  • Harness & connector (AID - ASV)
  • AID
  • ASV
  • ECM
80% Duty Ratio See  5waveform 5 AI System: OFF (Air pump OFF, ASV OFF) P1613 
  • AID
  • ECM
AI System: ON (Air pump ON, ASV ON) - Normal
Excluding Above (excluding 0, 20, 40, 80, 100% duty) - P1613 
  • AID
  • Open in AID ground circuit
  1. Waveform 1 

    100% Duty Ratio

    Fig 4: Waveform Graph (Waveform 1)
    G04967928Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  2. Waveform 2 

    0% Duty Ratio

    Fig 5: Waveform Graph (Waveform 2)
    G04967929Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  3. Waveform 3 

    20% Duty Ratio

    Fig 6: Waveform Graph (Waveform 3)
    G04967930Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  4. Waveform 4 

    40% Duty Ratio

    Fig 7: Waveform Graph (Waveform 4)
    G04967931Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  5. Waveform 5 

    80% Duty Ratio

    Fig 8: Waveform Graph (Waveform 5)
    G04967932Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    HINT:

    • Using the AIR INJ CHECK operation of the SYSTEM CHECK provided in the intelligent tester function, conditions for air fuel ratio and pressure in the secondary air injection system passage can be checked while the secondary air injection system is operating. It helps technicians to troubleshoot the system when it is malfunctioning.
    • Read freeze frame data using the intelligent tester. 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. INSPECT AIR PUMP 
      1. Remove the intake manifold (see REMOVAL ).
      2. Disconnect the A55 air pump connector.
      3. Measure the resistance of the air pump.

        Standard resistance 

        TESTER CONNECTION SPECIFIED CONDITION CHART

        Tester Connections Specified Conditions
        1 - 2 0.4 to 1.0 Ω
      4. Reconnect the air pump connector.

      NG: REPLACE AIR PUMP 

      Fig 9: Identifying Air Pump Connector Terminals
      G05190434Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      OK: GO TO Next Step 

    2. CHECK HARNESS AND CONNECTOR (AIR PUMP - BODY GROUND) 
      1. Remove the intake manifold (see REMOVAL ).
      2. Disconnect the A55 air pump connector.
      3. Measure the resistance of the wire harness side connectors and body ground.

        Standard resistance 

        TESTER CONNECTION SPECIFIED CONDITION CHART

        Tester Connection Specified Condition
        A55-2 - Body ground Below 1 Ω
      4. Reconnect the air pump connector.

      NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

      Fig 10: Identifying A55 Air Pump Connector Terminals
      G05196717Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      OK: GO TO Next Step 

    3. CHECK HARNESS AND CONNECTOR (AIR INJECTION CONTROL DRIVER - AIR PUMP) 
      1. Check harness and connector (see ELECTRONIC CIRCUIT INSPECTION PROCEDURE ).

      NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

      OK: REPLACE AIR INJECTION CONTROL DRIVER 

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