Description
OBD-II Trouble Code Description for P0166 Mazda
O2 Sensor Circuit No Activity Detected
What does this mean?
OBD2 Code P0166 Mazda definition:
The rear heated oxygen sensor (or sensor 3 for some vehicles), after three way catalyst (manifold), monitors the oxygen level in the exhaust gas on each bank. Even if switching characteristics of the heated oxygen sensor 1 are shifted, the air-fuel ratio is controlled to stoichiometric, by the signal from the heated oxygen sensor 3. This sensor is made of ceramic zirconia. The zirconia generates voltage from approximately 1V in richer conditions to 0V in leaner conditions. Under normal conditions the heated oxygen sensor 3 is not used for engine control operation.
Symptoms
Possible sumptoms of OBD code P0166 Mazda
– Engine Light ON (or Service Engine Soon Warning Light) – High Fuel Consumption – Excessive Smoke from Exhaust
Causes
Possible causes of OBD code P0166 Mazda
– Harness or connectors (The sensor circuit is open or shorted) – Rear heated oxygen sensor (Bank 2) may be faulty The Error code is generally activated on detection of the following conditions: Current amperage in the rear heated oxygen sensor heater circuit is out of the normal range. (An improper voltage drop signal is sent to ECM through the rear heated oxygen sensor heater
The OBD2 Code Information Be Applicable For Mazda:
2013 Mazda MX-5,2013 Mazda CX-9,2013 Mazda CX-5,2013 Mazda 6,2013 Mazda 5,2013 Mazda 3,2012 Mazda CX-5,2012 Mazda BT-50,2012 Mazda 3,2011 Mazda 6,2011 Mazda 5,2011 Mazda 2,2010 Mazda CX-7,2010 Mazda 3,2009 Mazda RX-8,2009 Mazda MX-5,2009 Mazda CX9,2009 Mazda 6,2009 Mazda 2,2008 Mazda MX-5,2008 Mazda 6,2008 Mazda 5,2008 Mazda 2,2007 Mazda CX-9,2007 Mazda CX-7,2006 Mazda MX5,2006 Mazda 6,2006 Mazda 3,2005 Mazda Atenza,2005 Mazda 6,2004 Mazda MPV,2004 Mazda 6,2004 Mazda 5,2004 Mazda 3,2003 Mazda RX-8
Note:
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