Technical Description
The Oxygen O2 Sensor Circuit is experiencing low voltage in Bank 1, Sensor 2.
What does that mean?
This diagnostic trouble code (DTC) is a generic powertrain code that applies to OBD-II equipped vehicles. While it is a generic code, the specific repair steps may vary depending on the make and model of the vehicle.
A P0136 code is essentially the same as P0137 and refers to the second oxygen sensor on Bank 1. The O2 oxygen sensor generates a voltage ranging from 0.1 V to 0.9 V. The ECM monitors the voltage of the O2 sensor to determine if the exhaust is lean or rich.
When the exhaust is rich, the O2 sensor voltage is high, and when the exhaust is lean, the O2 sensor voltage is low. The ECM monitors this voltage and adjusts the fuel injector pulsewidth accordingly to maintain the proper fuel/air ratio in the engine. If the ECM detects a low HO2Sensor voltage for an extended period, it will trigger the P0136 code. The specific conditions required to trigger this code may vary depending on the model of the vehicle and can be up to 4 minutes.
Symptoms
There may not be any visible symptoms for the driver. However, poor fuel mileage and possible misfires can occur depending on the position of the O2 sensor when it is sticking.
Causes
A P0136 code may indicate that one or more of the following issues have occurred:
