2008 Cadillac SRX Oxygen Sensor

Contamination of the oxygen sensor can result from the use of an inappropriate room temperature vulcanized silicone rubber (RTV) sealant (not oxygen sensor safe) or excessive engine coolant or oil consumption and you should remove the HO2S and visually inspect the portion of the sensor exposed to the exhaust stream to check for contamination. If contaminated, the portion of the sensor exposed to the exhaust stream will have a white powdery coating and silicon contamination causes a high but false HO2S signal voltage (rich exhaust indication). You should eliminate the source of contamination before replacing the oxygen sensor.

You should slide the lever lock forward while pressing down on the lever lock release tab, disconnect the connector from the component, locate the dress cover locking tabs at the corners of the dress cover, use a small flat-blade tool to release the locking tabs and remove the dress cover and a small flat-blade tool to slide the terminal position assurance (TPA) up one notch on both ends of the connector, gently pull the wire out of the back of the connector and always remember never use force when pulling a terminal out of a connector.

You should take care when handling the HO2S and the O2S, keep the in-line electrical connector and the louvered end free of grease, dirt, or other contaminants, avoid using cleaning solvents of any type, then turn the ignition off, disconnect the heated oxygen sensor (HO2S) electrical connector, remove the HO2S electrical connector from the wiring harness bracket, raise and support the vehicle and remove the HO2S from the catalytic converter.

You should not apply contact cleaner or other materials to the sensor or vehicle harness connectors or damage the sensor pigtail and harness wires in such a way that the wires inside are exposed. You should ensure the sensor or vehicle lead wires are not bent sharply or kinked, avoid removing or defeating the oxygen sensor ground wire, where applicable, and ensure that the peripheral seal remains intact on the vehicle harness connector to prevent damage due to water intrusion.

When replacing the HO2S, you should perform a code clear with a scan tool, regardless of whether or not a DTC is set and HO2S heater resistance learn reset with a scan tool, where available to reset the HO2S resistance learned value and avoid possible HO2S failure.