# P0139 on the 2010 Mazda Mazda5

The bulletins listed name this code in NHTSA's summary, or are about the same components. A bulletin or a recall listed here may apply to the model year. None of it is a diagnosis.

Nobody has written a description of this code yet.

## Bulletins for this model year that name P0139

- [10097702](https://open.wenmarpro.com/bulletins/10097702), 2017-04-21: SOME VEHICLES MAY EXPERIENCE THE MIL ON WITH DTC P0139 \(HO2S CIRCUIT MALFUNCTION\) STORED IN PCM MEMORY. THE PCM:1.MONITORS FOR A TIME\-OUT MALFUNCTION \(WHEN HO2S REMAINS ABOVE 0.2V FOR LONGER THAN A SPECIFIED PERIOD OF TIME DURING FUEL CUT CONTROL\).2.MEASURES THE AMOUNT OF TIME FROM WHEN CONDITIONS ARE MET UNTIL HO2S OUTPUT VOLTAGE DROPS BELOW 0.2V.3.DETERMINES A HO2S TIMEOUT MALFUNCTION WHEN THE DETECTED TIME IS MORE THAN 4 SECONDS FOR 2 OF 3 TIMES.THIS MAY BE CAUSED BY CARBON FORMING INSIDE THE ELECTRIC THROTTLE BODY \(ETB\) WHICH:1.REDUCES THE AIR INTAKE AMOUNT DURING DECELERATION \(WITH FUEL CUT\).2.ALLOWS FUEL TO REMAIN AROUND THE HO2S.3.CAUSES DETECTION OF P0139 \(HO2S TIME\-OUT FAIL\).