On-Vehicle Inspection

INSPECT MASS AIR FLOW METER

Check the mass air flow value.
1. Connect intelligent tester to the DLC3.
2. Turn the engine switch on (IG).
3. Push the intelligent tester main switch ON.
4. Enter the following menus: DIAGNOSIS / ENHANCED OBD II / DATA LIST / PRIMARY / MAF.
5. Blow air into the MAF meter, and check that the MAF value fluctuates.
  If the result is not as specified, check the MAF meter (see next procedure), or wiring and ECM.
  
  Fig 1: Blowing Air Into MAF Meter
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
Check the output voltage.
1. Disconnect the MAF meter connector and remove the 2 screws and MAF meter.
2. Apply battery voltage across terminals 1 (+B) and 2 (E2G).
  NOTE: While using the battery during inspection, do not bring the positive and negative tester probes too close to each other as a short circuit may occur.
3. Using a voltmeter, connect the positive (+) tester probe to terminal 3 (VG), and negative (-) tester probe to terminal 2 (E2G).
4. Blow air into the MAF meter, and check that the voltage fluctuates.
  If the result is not as specified, replace the MAF meter.
5. Reinstall the MAF meter with the 2 screws and connect the MAF meter connector.
  
  Fig 2: Identifying Output Voltage
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Check the IAT sensor.

Fig 3: Identifying IAT Sensor

G04018037

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Disconnect the MAF meter connector and remove the 2 screws and MAF meter.

Measure the resistance between terminals 4 (THA) and 5 (E2).

Standard resistance

TERMINALS RESISTANCE SPECIFICATIONS

Condition	Specified Condition
-20°C (14°F)	13.6 to 18.4 kΩ
20°C (68°F)	2.21 to 2.69 kΩ
60°C (140°F)	0.49 to 0.67 kΩ

If the result is not as specified, replace the MAF meter.

Reinstall the MAF meter with the 2 screws and connect the MAF meter connector.