DTC P050A Cold Start Idle Air Control System Performance: Description

2009 Toyota Sienna XLE, FWDSECTION Description

This monitor will run when the engine is started at -10 to 50°C (14 to 122°F) of the engine coolant temperature. The DTC will set after the engine idling for 13 seconds (2 trip detection logic).

The DTC is designed to monitor the idle air control at cold start. When the engine is started at lower than 50°C (122°F) of the engine coolant temperature, the ECM measures the accumulated mass airflow at the engine idling. If it does not reach the criteria within 10 seconds, the ECM interprets this as a malfunction.

The MIL is illuminated and a DTC is set when the malfunction is detected in consecutive driving cycles (2 trip detection logic).

The ETCS (Electrical Throttle Control System) controls the idle speed. The ETCS operates the throttle actuator to open and close the throttle valve, and adjusts the intake air amount to achieve the target idle speed.

NOTE: When the negative battery terminal is disconnected during inspection or repairs, the ISC (Idle Speed Control) learned values are cleared. ISC learning is performed when the engine has been warmed up and idled for 5 minutes because this DTC cannot be set after the ISC learned values cleared.
DTC TROUBLE DETECTION CHART

DTC No. DTC Detection Condition Trouble Area
P050A Accumulated intake air amount for 10 seconds of idling after cold start is less than threshold (2 trip detection logic)
  • Throttle body assembly
  • Mass air flow meter
  • Intake system
  • PCV hose connections
  • VVT system
  • Air cleaner filter element
  • ECM
RENDER: 1.0x

NO RELATED

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

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  • Brakes feel soft, pull hard to one side, or make grinding noises.
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