LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Lexus >> 2008 >> LX 570 >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System - DTC P0455 - P0657 >> DTC P050A Cold Start Idle Air Control System Performance >> Description
April 5, 2026: LEMON Manuals is launched! Read the announcement.

DTC P050A Cold Start Idle Air Control System Performance: Description

DTC DETECTION CONDITION CHART

DTC Code DTC Detection Condition Trouble Area
P050A Mass air flow is insufficient at cold start (2 trip detection logic).
  • Throttle body
  • Mass air flow meter
  • PCV hose
  • Air cleaner filter
  • Air induction system
  • VVT system
  • ECM

This monitor will run when the engine is started with the engine coolant temperature at -10 to 50°C (14 to 122°F). The DTC will be stored after the engine idles 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 with the engine coolant temperature at below 50°C (122°F), the ECM (PCM) measures the accumulated mass air flow at engine idling. If it does not reach the criteria within 10 seconds, the ECM (PCM) interprets this as a malfunction. The MIL is illuminated and a DTC is stored when the malfunction is detected in consecutive driving cycles (2 trip detection logic).

The ETCS (Electronic 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 cable is disconnected from the negative (-) battery terminal during inspections or repairs, the ISC (Idle Speed Control) learning values are cleared. This DTC cannot be stored with the ISC learning values cleared.
The ISC learning is performed when the engine is warmed up and has been idling for 5 minutes.
Fig 1: Cold Start Idle Air Control System Performance Graph
G05149847Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002