Advanced Diagnostics
Advanced Diagnostics - DTC P0157: Front Secondary Heated Oxygen Sensor (Secondary HO2S (Bank 2, Sensor 2)) Circuit Low VoltageGeneral Description
The front secondary heated oxygen sensor (secondary HO2S (bank 2, sensor 2)) detects the oxygen density in the exhaust gas and converts it into electrical signals. If the front secondary HO2S (bank 2, sensor 2) output voltage is a specified value for a set time, the powertrain control module (PCM) detects a malfunction and stores a DTC.
Monitor Execution, Sequence, Duration, DTC Type, OBD Status
Enable Conditions
Malfunction Threshold
The front secondary HO2S (bank 2, sensor 2) output voltage is 0.12 V or less for at least 5 seconds.
Confirmation Procedure
With the Driving Pattern
Start the engine. Hold the engine speed at 3,000 rpm without load (in P or N) until the radiator fan comes on, then let it idle.
Diagnosis Details
Conditions for setting the DTC
When a malfunction is detected during the first drive cycle, a Pending DTC is stored in the PCM memory. If the malfunction returns in the next (second) drive cycle, the MIL comes on and a Confirmed DTC and the freeze data are stored.
Conditions for clearing the DTC
The MIL is cleared if the malfunction does not return in three consecutive trips in which the diagnostic runs. The MIL, the Pending DTC, the Confirmed DTC, and the freeze data can be cleared with the scan tool Clear command or by disconnecting the battery.