General Information
Engine Control
P0133 O2 Sensor Circuit Slow Response (Bank 1 / Sensor 1) - General Information
Component Location
General Description
Lambda sensor installed at exhaust manifold is planar ZrO2 dual cell type and it senses O2 density of exhaust gas for accurate EGR control through fuel correction. It also limits smoke which is generated by reach air-fuel mixture at engine maximum loading condition. ECM controls pumping current in order to fit lamda-value from linear O2 sensor to 1.0.
Lean air-fuel mixture(1.0
Heater coil is controlled by ECM as PWM. the resistance of heater coil is low when coil is cold thus, current through it increases while resistance is high when coil is hot thus, current decreases. With this principle, Lambda sensor temp. is measured and Lambda sensor heater operation varies based on the data.
DTC Description
If there is abnormal response rate of HO2S under enable conditions, ECM sets DTC P0133.
(This DTC might be caused by the malfunction of Heater circuit, so, check the heater circuit first. )
DTC Detecting Condition
** S1 : upstream oxygen sensor / S2 : downstream oxygen sensor
Diagnostic Circuit Diagram
Signal Waveform & Data
Waveform of sensor Current Pump at IG KEY "ON" and Engine running. It fluctuates between 2V and 3V periodically.
Waveform of sensor Vertual Ground Output at IG KEY "ON" and Engine running. 2.5V is displayed.
Waveform of sensor Current Adjust at IG KEY "ON" and Engine running. It fluctuates between 2V and 3V periodically. Waveform of sensor Nernst Voltage at IG KEY "ON" and Engine running. 2.9V is displayed.