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Home >> Lexus >> 2011 >> IS F >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System (Diagnostic Codes (P0171-P0607) >> SFI System >> DTC P050B: Cold Start Ignition Timing Performance >> Description
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DTC P050B: Cold Start Ignition Timing Performance: Description

This monitor will run when the engine is started at an engine coolant temperature of -10 to 60°C (14 to 140°F). The DTC will be stored after the engine idles for 13 seconds (2 trip detection logic).

The DTC is designed to monitor the ignition timing at cold start. When the engine is started at an engine coolant temperature of below 60°C (140°F), the ECM checks the ignition timing during engine idling. If the ignition timing advances beyond the specified level within 10 seconds, the ECM 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).

NOTE:

When the cable is disconnected from the negative battery terminal during inspections or repairs, the ISC (Idle Speed Control) learned values are cleared. This DTC cannot be stored with the ISC learned values cleared.

HINT: 

ISC learning is performed when the engine is warmed up and has been idling for 5 minutes.

Fig 1: Identifying ISC Learning Value Graph
GTY356082Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
DTC No. DTC Detection Condition Trouble Area
P050B Insufficient ignition timing related at cold start (2 trip detection logic)
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