P0166 Citroen O2 Sensor Circuit No Activity Detected Bank 2 Sensor 3

P0166 Citroen O2 Sensor Circuit No Activity Detected Bank 2 Sensor 3

Possible causes
– Faulty Heated Oxygen Sensor Bank 2 Sensor 3
– Heated Oxygen Sensor Bank 2 Sensor 3 harness is open or shorted
– Heated Oxygen Sensor Bank 2 Sensor 3 circuit poor electrical connection
Tech description
Replacing the O2 Sensor 3 usually takes care of the problem
What about the obd code?
Current amperage in the rear heated oxygen sensor heater circuit has no activity.
Symptoms
– Engine Light ON (or Service Engine Soon Warning Light)
– High Fuel Consumption
– Excessive Smoke from Exhaust
P0166 Citroen Description

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.

P0166 Citroen Information for specific makes
P0166 Citroen HONDA
Citroen Vehicle:2013 Citroen,2012 Citroen,2011 Citroen,2010 Citroen,2009 Citroen,2008 Citroen,2007 Citroen,2006 Citroen,2005 Citroen,2004 Citroen,2003 Citroen,2002 Citroen,2001 Citroen,2000 Citroen,1999 Citroen,1998 Citroen,1997 Citroen,1996 Citroen,