2009 Toyota Matrix Base, AutomaticFACTORY OEM SERVICE PROCEDURE

DTC P0101 Mass Air Flow Circuit Range / Performance Problem: Description

Refer to DTC P0102 (See DTC P0102 MASS OR VOLUME AIR FLOW CIRCUIT LOW INPUT; DTC P0103 MASS OR VOLUME AIR FLOW CIRCUIT HIGH INPUT ).

DTC DETECTION CONDITION CHART

DTC No. DTC Detection Condition Trouble Area
P0101 Conditions (a), (b), (c), (d) and (e) continue for more than 10 seconds (2 trip detection logic):
  1. Engine running
  2. Engine coolant temperature 70°C (158°F) or higher
  3. Throttle position sensor voltage 0.24 to 2 V
  4. Average engine load value ratio less than 0.85, or more than 1.28 (varies with estimated engine load) Average engine load value ratio = Average engine load based on mass air flow meter output / Average engine load estimated from driving conditions
  5. Average air fuel ratio less than -20%, or more than 20%
  • Mass air flow meter
  • Intake system
  • PCV hose connections
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