Mazda CX-5 2014–2016 — technical service bulletin
Bulletin 01-016-15-3067 · NHTSA communication 10105502 · issued Aug 4, 2015
Technical service bulletin
communication type
Equipment
component
2014–2016
model years
7
vehicle entries
Official summary
Some vehicles may experience the check engine light on with dtc p0421:00 (catalytic converter system) without experiencing poor engine performance or misfire (mitsubishi pcm only). This is caused by improper control logic of the pcm that may detect false error of the a/f sensor, resulting in false detection of p0421. To correct the problem, the control logic of the pcm has been changed. Catalyst monitor function explanation the pcm monitors the oxygen storage amount proportional to catalytic converter purification characteristic. The pcm starts to monitor after recovery (fuel injection starts)
Vehicles covered
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.