Inspection Procedure

HINT:

• If other DTCs relating to different systems that have terminal E2 as the ground terminal are output simultaneously, terminal E2 may have an open circuit.
• Read freeze frame data using Techstream. The ECM (Included in HV control ECU) records vehicle and driving condition information as freeze frame data the moment a DTC is stored. 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. READ VALUE USING TECHSTREAM (INTAKE AIR TEMPERATURE) 
   1. Connect Techstream to the DLC3.
   2. Turn the ignition switch to the ON position.
   3. Turn the tester ON.
   4. Enter the following menus: Powertrain / Engine and ECT / Data List / All Data / Intake Air.
   5. Read the value displayed on the tester.

      Standard: 

      Same as actual Intake Air Temperature (IAT). 

      Result 

      RESULT CHART
      
      

      Temperature Displayed	Proceed to
      -40°C (-40°F)	A
      140°C (284°F) or higher	B
      Same as actual IAT	C

      HINT:

      • If there is an open circuit, Techstream indicates -40°C (-40°F).
      • If there is a short circuit, Techstream indicates 140°C (284°F) or higher.

   B: Go to step  4

   C: CHECK FOR INTERMITTENT PROBLEMS 

   A: Go to next step 

2. READ VALUE USING TECHSTREAM (CHECK FOR OPEN IN WIRE HARNESS) 
   1. Disconnect the M1 Mass Air Flow (MAF) meter connector.
   2. Connect terminals THA and E2 of the MAF meter wire harness side connector.
   3. Connect Techstream to the DLC3.
   4. Turn the ignition switch to the ON position.
   5. Turn the tester ON.
   6. Enter the following menus: Powertrain / Engine and ECT / Data List / All Data / Intake Air.
   7. Read the value displayed on the tester.

      Standard: 

      140°C (284°F) or higher 

   8. Reconnect the MAF meter connector.
   Fig 1: Identifying Terminals Of M1 MAF Meter Connector
   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   OK: CONFIRM GOOD CONNECTION TO SENSOR. IF OK, REPLACE MASS AIR FLOW METER 

   NG: Go to next step 

3. READ VALUE USING TECHSTREAM (CHECK FOR OPEN IN HV CONTROL ECU) 
   1. Disconnect the M1 MAF meter connector.
   2. Connect terminals THA and E2 of the H32 HV control ECU connector.

      HINT:

      Before checking, do visual and contact pressure checks on the HV control ECU connector.

   3. Connect Techstream to the DLC3.
   4. Turn the ignition switch to the ON position.
   5. Turn the tester ON.
   6. Enter the following menus: Powertrain / Engine and ECT / Data List / All Data / Intake Air.
   7. Read the value displayed on the tester.

      Standard: 

      140°C (284°F) or higher 

   8. Reconnect the MAF meter connector.
   Fig 2: Identifying Terminals Of H32 HV Control ECU Connector
   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   OK: REPAIR OR REPLACE HARNESS OR CONNECTOR 

   NG: CONFIRM GOOD CONNECTION TO HV CONTROL ECU. IF OK, REPLACE HV CONTROL ECU 

4. READ VALUE USING TECHSTREAM (CHECK FOR SHORT IN WIRE HARNESS) 
   1. Disconnect the M1 MAF meter connector.
   2. Connect Techstream to the DLC3.
   3. Turn the ignition switch to the ON position.
   4. Turn the tester ON.
   5. Enter the following menus: Powertrain / Engine and ECT / Data List / All Data / Intake Air.
   6. Read the value displayed on the tester.

      Standard: 

      -40°C (-40°F) or higher 

   7. Reconnect the MAF meter connector.
      Fig 3: Identifying MAF Meter Connector

      Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   OK: REPLACE MASS AIR FLOW METER 

   NG: Go to next step 

5. READ VALUE USING TECHSTREAM (CHECK FOR SHORT IN HV CONTROL ECU) 
   1. Disconnect the H32 HV control ECU connector.
   2. Connect Techstream to the DLC3.
   3. Turn the ignition switch to the ON position.
   4. Turn the tester ON.
   5. Enter the following menus: Powertrain / Engine and ECT / Data List / All Data / Intake Air.
   6. Read the value displayed on the tester.

      Standard: 

      -40°C (-40°F) or higher 

   7. Reconnect the HV control ECU connector.
   Fig 4: Identifying Terminals Of H32 HV Control ECU Connector
   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   OK: REPAIR OR REPLACE HARNESS OR CONNECTOR 

   NG: REPLACE HV CONTROL ECU