DSD Information System
Home >> Toyota >> 2021 >> Highlander LE, 4WD >> Repair and Diagnosis >> External Pages >> Different variant/trim >> Section 56 (Engine Control System (A25A-FXS) - Diagnostic Codes (P11EA-P12D0)) >> SFI System >> DTC P11EA-00: Bank 1 Air-Fuel Ratio Imbalance (Port); DTC P11EC-00: Cylinder #1 Air-Fuel Ratio Imbalance (Port); DTC P11ED-00: Cylinder #2 Air-Fuel Ratio Imbalance (Port); DTC P11EE-00: Cylinder #3 Air-Fuel Ratio Imbalance (Port); DTC P11EF-00: Cylinder #4 Air-Fuel Ratio Imbalance (Port); DTC P219A-00: Bank 1 Air-Fuel Ratio Imbalance; DTC P219C-00: Cylinder 1 Air-Fuel Ratio Imbalance; DTC P219D-00: Cylinder 2 Air-Fuel Ratio Imbalance; DTC P219E-00: Cylinder 3 Air-Fuel Ratio Imbalance; DTC P219F-00: Cylinder 4 Air-Fuel Ratio Imbalance [11/2023 - ] >> Monitor Description

Monitor Description

WARNING: This page is about a different variant/trim than selected.

Fuel System Air Fuel Ratio Cylinder Imbalance Monitor 

The ECM uses the air fuel ratio sensor (sensor 1) and crankshaft position sensor to monitor the difference in air fuel ratios between the cylinders caused by differences in injection volumes between the cylinders, leakage in the intake or exhaust system, etc.

When the air fuel ratios of the cylinders are lean or rich with respect to each other, the ECM determines that there is a malfunction, illuminates the MIL and stores a DTC.

Air Fuel Ratio Sensor (Sensor 1) Monitoring Method: P11EA-00 (for port injection), or P219A-00 (for direct injection) is stored primarily when a rich side imbalance is detected. 

When the system detects a difference in air fuel ratios between the cylinders due to fluctuation in the air fuel ratio sensor (sensor 1) output over 1 engine cycle (2 crankshaft revolutions), the system determines that there is a problem.

Crankshaft Position Sensor Monitoring Method: P11EC-00, P11ED-00, P11EE-00 and/or P11EF-00 (for port injection), or P219C-00, P219D-00, P219E-00 and/or P219F-00 (for direct injection) are stored primarily when a lean side imbalance is detected. 

The system monitors the engine speed variation and when the variation becomes large, the system determines that there is a difference in air fuel ratios between the cylinders, which it determines to be a problem.

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