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Service bulletin B121615

A bulletin is a manufacturer's communication to its dealers, as NHTSA indexes it. The summary is NHTSA's. The document is the manufacturer's: read it at NHTSA. A bulletin is not a recall, and listing a model year does not mean every vehicle of it is concerned.

The communication, as NHTSA indexes it (as of 2026-10-19)
TypeService bulletin
NHTSA id10147665
Published by NHTSA2018-11-13
Manufacturer's numberB121615
Manufacturer's date2015-03-01
NHTSA componentENGINE; ENGINE AND ENGINE COOLING:EXHAUST SYSTEM:EMISSION CONTROL:CATALYTIC CONVERTOR

NHTSA's 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.

The document

The document is the manufacturer's. This site does not hold it. NHTSA files a document at one of these two addresses; we have not asked NHTSA which.

Components

Engine, Exhaust and emissions, Catalytic converter

Vehicles listed
BMW 1 SERIES M2011 to 2013
BMW 525D XDRIVE2014
BMW 550I2011, 2012, 2013, 2014, 2015, 2016
BMW 550I GRAN TURISMO2010, 2011, 2012 (the catalog's model; the bulletin names a series or trim of it)
BMW 650I2012, 2013, 2014, 2015, 2016
BMW 750I2009, 2010, 2011, 2012, 2013, 2014, 2015
BMW 750LI2009, 2010, 2011, 2012, 2013, 2014, 2015
BMW ACTIVE HYBRID 72012
BMW ACTIVE HYBRID 72014
BMW ACTIVEHYBRID 72011
BMW X52014, 2015, 2016

Listing a model year does not mean every vehicle of it is concerned: the document says which.

Other bulletins for the same vehicles and component
B1223192019-08-19. Service bulletin. DIAGNOSTIC HINT: CATALYTIC CONVERTER INSPECTION AFTER LOSS OF CRANKSHAFT SIGNAL. In certain situations when the crankshaft position signal is lost while driving the malfunction indicator lamp (MIL) and an engine malfunction check control message (CCM #29) may be displayed. The engine may run roughly or with reduced power.