Advanced Diagnostics

Advanced Diagnostics - DTC P0137: Secondary Heated Oxygen Sensor (Secondary HO2S (Sensor 2)) Circuit Low Voltage (Engine Type: K24Z7)

General Description






The secondary heated oxygen sensor (secondary HO2S (sensor 2)) detects the oxygen density in the exhaust gas and converts it into electrical signals. If the secondary HO2S (sensor 2) output voltage is a specified value for a set time, the engine control module (ECM) detects a malfunction and stores a DTC.

Monitor Execution, Sequence, Duration, DTC Type, OBD Status






Enable Conditions






Malfunction Threshold
The secondary HO2S (sensor 2) output voltage is 0.12 V or less for at least 5 seconds.

Possible Cause

NOTE: The causes shown may not be a complete list of all potential problems, and it is possible that there may be other causes.

- Secondary HO2S (sensor 2) SO2 line short to ground
- Secondary HO2S (sensor 2) SO2_SG line short to ground
- ECM internal circuit failure

Confirmation Procedure

With the HDS
None.

With the Driving Pattern
Start the engine. Hold the engine speed at 3,000 rpm without load (in neutral) 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 ECM 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.