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RecallGazette

Vehicle problems, recalls & safety intelligence

BMW 1 Series M 2009–2016technical service bulletin

Bulletin B121615 · NHTSA communication 10147665 · issued Mar 1, 2015

Technical service bulletin
communication type
Engine
component
2009–2016
model years
38
vehicle entries

Official summary

N63T: Oxygen Sensor Internal Resistance Faults. The Service Engine Soon light comes on with either or both of the following faults stored in the DME memory: ? 12B701 - Oxygen sensor heating after catalytic converter, function: Internal resistance too high ? 12B801 - Oxygen sensor heating after catalytic converter 2, function: Internal resistance too high The engine operation and performance are not affected. The DME diagnosis for the post catalyst oxygen sensor(s) is too sensitive.

What a TSB means. Technical service bulletins are repair guidance manufacturers send to dealers — they are not recalls, and repairs are not automatically free (warranty extensions are an exception worth checking). The full document is available via NHTSA’s vehicle lookup.