P0166 Cadillac 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
– 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
– High Fuel Consumption
– Excessive Smoke from Exhaust
P0166 Cadillac 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 Cadillac Information for specific makes
P0166 Cadillac HONDA
Cadillac Vehicle:Cadillac CTS Coupe, Cadillac CTS-V Coupe , Cadillac Eldorado , Cadillac Escalade EXT , Cadillac ATS , Cadillac CTS , Cadillac CTS Sedan , Cadillac CTS Sport Sedan , Cadillac CTS-V , Cadillac CTS-V Sedan , Cadillac Catera , Cadillac DTS , Cadillac DeVille , Cadillac STS-V , Cadillac STS , Cadillac Seville , Cadillac XTS , Cadillac XLR , Cadillac XLR Platinum , Cadillac Escalade , Cadillac SRX