Inspection Procedure

WARNING: This page is about a different car, the 2007 Lexus SC 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 VALUE OF INTELLIGENT TESTER (INTAKE AIR TEMPERATURE)

Connect the intelligent tester to the CAN VIM. Then connect the CAN VIM to the DLC3.
Turn the ignition switch ON and turn the tester ON.
Enter the following menus: DIAGNOSIS / ENHANCED OBD II / DATA LIST / ALL / INTAKE AIR.

Read the values.

OK:

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 VALUE OF INTELLIGENT TESTER (CHECK FOR OPEN IN WIRE HARNESS)
1. Disconnect the M1 MAF meter connector.
2. Connect terminal THA and E2 of the MAF meter's wire harness side connector.
  
  Fig 1: Identifying THA And E2 Of MAF Meter Wire Harness Side Connector Terminals
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
3. Connect the intelligent tester to the CAN VIM. Then connect the CAN VIM to the DLC3.
4. Turn the ignition switch ON and turn the tester ON.
5. Enter the following menus: DIAGNOSIS / ENHANCED OBD II / DATA LIST / ALL / INTAKE AIR.
6. Read the value.
  OK:
  
  Temperature value is 140C (284°F) or more
OK: REPLACE MASS AIR FLOW METER

NG: Go to next step
READ VALUE OF INTELLIGENT TESTER (CHECK FOR OPEN IN ECM)
1. Disconnect the M1 MAF meter connector.
2. Connect terminal THA of the E4 ECM connector and terminal E2 of the E2 ECM connector.
  
  Fig 2: Identifying THA Of E4 ECM And E2 Of E2 ECM Connector Terminals
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  
  HINT:
  
  Before checking, perform 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 ignition switch ON and turn the tester ON.
5. Enter the following menus: DIAGNOSIS / ENHANCED OBD II / DATA LIST / ALL / INTAKE AIR.
6. Read the value.
  OK:
  
  Temperature value is 140°C (284°F) or more
NG: REPLACE ECM

OK: REPAIR OR REPLACE HARNESS AND CONNECTOR
READ VALUE OF INTELLIGENT TESTER (CHECK FOR SHORT IN WIRE HARNESS)
1. Disconnect the M1 MAF meter connector.
  
  Fig 3: Checking M1 MAF Meter And ECM Wire Harness
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
2. Connect the intelligent tester to the CAN VIM. Then connect the CAN VIM to the DLC3.
3. Turn the ignition switch ON and turn the tester ON.
4. Enter the following menus: DIAGNOSIS / ENHANCED OBD II / DATA LIST / ALL / INTAKE AIR.
5. Read the value.
  OK:
  
  Temperature value is -40°C (-40°F) or more
OK: REPLACE MASS AIR FLOW METER

NG: Go to next step
READ VALUE OF INTELLIGENT TESTER (CHECK FOR SHORT IN HARNESS OR ECM)
1. Disconnect the M1 MAF meter connector.
2. Disconnect the E2 and E4 ECM connectors.
  
  Fig 4: Disconnecting E2 And E4 ECM Connector Terminals
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
3. Connect the intelligent tester to the CAN VIM. Then connect the CAN VIM to the DLC3.
4. Turn the ignition switch ON and turn the tester ON.
5. Enter the following menus: DIAGNOSIS / ENHANCED OBD II / DATA LIST / ALL / INTAKE AIR.
6. Read the value.
  OK:
  
  Temperature value is -40°C (-40°F) or more
NG: REPLACE ECM

OK: REPAIR OR REPLACE HARNESS AND CONNECTOR