Mass Air Flow Meter: Inspection

INSPECT OUTPUT VOLTAGE
1. Apply battery voltage across terminals 1 (+B) and 2 (E2G).
2. Connect the positive (+) tester probe to terminal 3 (VG), and the negative (-) tester probe to terminal 2 (E2G).
3. Blow air into the MAF meter, and check if the voltage fluctuates.
INSPECT RESISTANCE
1. Using an ohmmeter, measure the resistance between terminals 4 (THA) and 5 (E2).
  Resistance:
  
  12.5 to 16.9 kΩ at -20°C (-4°F)
  
  2.19 to 2.67 kΩ at 20°C (68°F)
  
  0.50 to 0.68 kΩ at 60°C (140°F)
  
  Fig 1: Resistance And Temperature Graph
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
INSPECT MASS AIR FLOW METER
1. If using a intelligent tester:
  1. Connect the intelligent tester to the DLC3.
  2. Turn the ignition switch to the ON position.
  3. Blow air into the MAF meter, and check that the air flow value of the CURRENT DATA changes.
    If operation is not as specified, check the MAF meter (see DTC P0101 MASS AIR FLOW CIRCUIT RANGE / PERFORMANCE PROBLEM and DTC P0110 INTAKE AIR TEMPERATURE CIRCUIT; DTC P0112 INTAKE AIR TEMPERATURE CIRCUIT LOW INPUT; DTC P0113 INTAKE AIR TEMPERATURE CIRCUIT HIGH INPUT ) as well as the wiring and the ECM.
2. If not using a intelligent tester:
  1. Turn the ignition switch to the ON position.
    
    Fig 2: Blowing Air Into MAF Meter
    Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  2. Connect the positive tester probe of the voltmeter to terminal VG of the ECM and the negative tester probe of the voltmeter to terminal E2G of the ECM.
  3. Blow air into the air flow meter, and check if the voltage fluctuates.
    If operation is not as specified, check the MAF meter (See DTC P0101 MASS AIR FLOW CIRCUIT RANGE / PERFORMANCE PROBLEM and DTC P0110 INTAKE AIR TEMPERATURE CIRCUIT; DTC P0112 INTAKE AIR TEMPERATURE CIRCUIT LOW INPUT; DTC P0113 INTAKE AIR TEMPERATURE CIRCUIT HIGH INPUT ), the wiring and the ECM.
    
    Fig 3: Connecting Positive Tester Probe Of Voltmeter To Terminal VG Of ECM
    Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002