If the sensor output is below 0.06V and the average of voltage difference between loaded and unloaded voltage is below 0.015V under enable conditions, the ECM/PCM sets DTC P0137.
Item | Detecting Condition | Possible Cause |
DTC Strategy |
•
Voltage Range check | 1. Poor connection 2. Short to ground in signal circuit 3. HO2S(S2) |
Enable Conditions |
•
Lambda close loop control active
•
Lambda controller not at max. limit < 50%
•
Catalyst Purge after Fuel cut off not active
•
10V < Battery voltage < 16V | |
Threshold Value |
•
Downstream O2 Sensor Voltage < 0.02V
•
Downstream O2 sensor element resistance < 15Ω | |
Diagnostic Time |
•
35 sec | |
Mil On Condition |
•
2 driving cycles. |
※ S1 : upstream oxygen sensor / S2 : downstream oxygen sensor
