Inspection Procedure

WARNING: This page is about a different car, the 2007 Lexus GS 430. However, it is still accessible from the selected car via links, so may be relevant.

HINT:

Read freeze frame data using the intelligent tester. Freeze frame data records the engine conditions when a malfunction is detected. When troubleshooting, freeze frame data can help determine if the vehicle was running or stopped, 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.

READ DATA LIST (INTAKE AIR TEMPERATURE)

Connect the intelligent tester to the CAN VIM. Then connect the CAN VIM to the DLC3.
Turn the engine switch on (IG) and turn the tester ON.
Enter the following menus: DIAGNOSIS / ENHANCED OBD II / DATA LIST / ALL / INTAKE AIR.
Read the values.
Standard:

Same value as the actual IAT.

Result

RESULT CHART

Intake Air Temperature	Proceed to
-40°C (-40°F)	A
140°C (284°F) or more	B
OK (same as present temperature)	C

HINT:

If there is an open circuit, the intelligent tester indicates -40°C (-40°F).

If there is a short circuit, the intelligent tester indicates 140°C (284°F) or more.

B: Go to step 4

C: CHECK FOR INTERMITTENT PROBLEMS

A: Go to next step

READ DATA LIST (CHECK FOR OPEN IN WIRE HARNESS)
1. Disconnect the E42 MAF meter connector.
2. Connect terminals THA of the MAF meter's wire harness side connector.
3. Connect the intelligent tester to the CAN VIM. Then connect the CAN VIM to the DLC3.
4. Turn the engine switch on (IG) and turn the tester ON.
5. Enter the following menus: DIAGNOSIS / ENHANCED OBD II / DATA LIST / ALL / INTAKE AIR.
6. Read the value.
  Standard:
  
  140°C (284°F) or more
  
  Fig 1: Identifying E42 MAF Meter Connector
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
OK: REPLACE MASS AIR FLOW METER

NG: Go to next step
READ DATA LIST (CHECK FOR OPEN IN ECM)
1. Disconnect the E42 MAF meter connector.
2. Connect terminals THA of the E6 ECM connector and terminal E2 of the E8 ECM connectors.
  HINT:
  
  Before checking, do a visual and contact pressure check for the ECM connector.
3. Connect the intelligent tester to the CAN VIM. Then connect the CAN VIM to the DLC3.
4. Turn the engine switch on (IG) and turn the tester ON.
5. Enter the following menus: DIAGNOSIS / ENHANCED OBD II / DATA LIST / ALL / INTAKE AIR.
6. Read the value.
  Standard:
  
  140°C (284°F) or more
  
  Fig 2: Identifying E42 MAF Meter Connector And E6 ECM Connector Terminal
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
NG: REPLACE ECM

OK: REPAIR OR REPLACE HARNESS AND CONNECTOR
READ DATA LIST (CHECK FOR SHORT IN WIRE HARNESS)
1. Disconnect the E42 MAF meter connector.
2. Connect the intelligent tester to the CAN VIM. Then connect the CAN VIM to the DLC3.
3. Turn the engine switch on (IG) and turn the tester ON.
4. Enter the following menus: DIAGNOSIS / ENHANCED OBD II / DATA LIST / ALL / INTAKE AIR.
5. Read the value.
  Standard:
  
  -40°C (-40°F) or more
  
  Fig 3: Identifying E42 MAF Meter Connector
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
OK: REPLACE MASS AIR FLOW METER

NG: Go to next step
READ DATA LIST (CHECK FOR SHORT IN HARNESS OR ECM)
1. Disconnect the E42 MAF meter connector.
2. Disconnect the E6 and E8 ECM connectors.
3. Connect the intelligent tester to the CAN VIM. Then connect the CAN VIM to the DLC3.
4. Turn the engine switch on (IG) and turn the tester ON.
5. Enter the following menus: DIAGNOSIS / ENHANCED OBD II / DATA LIST / ALL / INTAKE AIR.
6. Read the value.
  Standard:
  
  -40°C (-40°F) or more
  
  Fig 4: Identifying E6 And E8 ECM Connectors
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
NG: REPLACE ECM

OK: REPAIR OR REPLACE HARNESS AND CONNECTOR