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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
01-025-13-28222017-04-21. Service bulletin. 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).

1 on file from NHTSA, as of 2026-10-19. See them in the bulletin list. A bulletin lists model years: read the document for which vehicles it concerns.