Inspection Procedure
NOTE:
- If different DTCs related to different systems that have terminal E2 as the ground terminal are output simultaneously, terminal E2 may be open.
- Read freeze frame data using the hand-held tester or the OBD II scan tool. Freeze frame data records the engine conditions when a malfunction is detected. When troubleshooting, it is useful for determining whether the vehicle was running or stopped, the engine was warmed up or not, the air-fuel ratio was lean or rich, etc. at the time of the malfunction.
- READ VALUE OF HAND-HELD TESTER OR OBD II SCAN TOOL(INTAKE AIR TEMPERATURE)
- Connect the hand-held tester or the OBD II scan tool to the DLC3.
- Turn the ignition switch ON and push the hand-held tester or the OBD II scan tool main switch ON.
- Select the item "DIAGNOSIS / ENHANCED OBD II / DATA LIST / ALL / INTAKE AIR" and read its value displayed on the hand-held tester or the OBD II scan tool.
Temperature: Same value as the actual intake air temperature.
Result:
DESCRIPTIONTemperature Displayed Proceed to -40°C (-40°F) A 140°C (284°F) or more B OK (Same as air temperature near to the intake) C NOTE:- If there is an open circuit, the hand-held tester or the OBD II scan tool indicates -40°C (-40°F).
- If there is a short circuit, the hand-held tester or the OBD II scan tool indicates 140°C (284°F) or more.
- B: Go to step 4
- C: CHECK FOR INTERMITTENT PROBLEMS (See CHECK FOR INTERMITTENT PROBLEMS )
- A: Go to next step.
- READ VALUE OF HAND-HELD TESTER OR OBD II SCAN TOOL(CHECK FOR OPEN IN WIRE HARNESS)
- Disconnect the M1 mass air flow sensor connector.
- Connect terminals THA and E2 of the mass air flow sensor wire harness side connector.
- Turn the ignition switch ON.
- Select the item "DIAGNOSIS / ENHANCED OBD II / DATA LIST / ALL / INTAKE AIR" and read its value displayed on the hand-held tester or the OBD II scan tool.
Temperature value: 140°C (284°F) or more
- Reconnect the mass air flow sensor connector.
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
- OK: CONFIRM GOOD CONNECTION AT SENSOR. IF OK, REPLACE MASS AIR FLOW SENSOR
- NG: Go to next step.
- READ VALUE OF HAND-HELD TESTER OR OBD II SCAN TOOL(CHECK FOR OPEN IN ECM)
- Disconnect the M1 mass air flow sensor connector.
- Connect the terminals THA and E2 of the E3 ECM connector.NOTE:
Before checking, do a visual and contact pressure check on the ECM connector.
- Turn the ignition switch ON.
- Select the item "DIAGNOSIS / ENHANCED OBD II / DATA LIST / ALL / INTAKE AIR" and read its value displayed on the hand-held tester or the OBD II scan tool.
Temperature value: 140°C (284°F) or more
- Reconnect the mass air flow sensor connector.
- OK: REPAIR OR REPLACE HARNESS OR CONNECTOR
- NG: CONFIRM GOOD CONNECTION AT ECM. IF OK, REPLACE ECM (See REPLACEMENT )
- READ VALUE OF HAND-HELD TESTER OR OBD II SCAN TOOL(CHECK FOR SHORT IN WIRE HARNESS)
- Disconnect the M1 mass air flow sensor connector.
- Turn the ignition switch ON.
- Select the item "DIAGNOSIS / ENHANCED OBD II / DATA LIST / ALL / INTAKE AIR" and read its value displayed on the hand-held tester or the OBD II scan tool.
Temperature value: -40°C (-40°F)
- Reconnect the mass air flow sensor connector.
- OK: REPLACE MASS AIR FLOW SENSOR
- NG: Go to next step.
- READ VALUE OF HAND-HELD TESTER OR OBD II SCAN TOOL(CHECK FOR SHORT IN ECM)
- Disconnect the E3 ECM connector.
- Turn the ignition switch ON.
- Select the item "DIAGNOSIS / ENHANCED OBD II / DATA LIST / ALL / INTAKE AIR" and read its value displayed on the hand-held tester or the OBD II scan tool.
Temperature value: -40°C (-40°F)
- Reconnect the ECM connector.
- OK: REPAIR OR REPLACE HARNESS OR CONNECTOR
- NG: REPLACE ECM (See REPLACEMENT )