Fixing BMW O2 Sensors

Feb. 27, 2023

This bulletin applies to 2015 BMW vehicles equipped with the N63T engine. The Service Engine Soon light may be on, accompanied by DTCs 12B701 (oxygen sensor heating after catalytic converter, function, internal resistance too high) and/or 12B801 (oxygen sensor heating after catalytic converter two, function, internal resistance too high). 

This bulletin applies to 2015 BMW vehicles equipped with the N63T engine. The Service Engine Soon light may be on, accompanied by DTCs 12B701 (oxygen sensor heating after catalytic converter, function, internal resistance too high) and/or 12B801 (oxygen sensor heating after catalytic converter two, function, internal resistance too high). 

Engine performance and operation may not be affected. The cause of the DCTs: the DME diagnosis for the post catalyst oxygen sensor(s) is too sensitive. According to BMW, do not replace any parts for this concern. Perform diagnosis with the latest version of ISTA, and re-program the vehicle using the latest version of ISTA/P.

About the Author

Information courtesy of Mitchell 1

Information for Technical Service Bulletins comes from ProDemand, Mitchell 1's auto repair information software for domestic and import vehicles. Headquartered in San Diego, Mitchell 1 has provided quality repair information solutions to the automotive industry since 1918.

About the Author

Mike Mavrigian | Motor Age Editor

Mike Mavrigian has written thousands of automotive technical magazine articles involving a variety of  specialties, from engine building to wheel alignment, and has authored more than a dozen books that crisscross the automotive spectrum. Mike operates Birchwood Automotive, an Ohio shop that builds custom engines and performs vintage vehicle restorations. The shop also features a professional photo studio to document projects and to create images for articles and books.

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