Im looking for information anyone might have on the P2237 air/fuel sensor code. This weekend I went to have my 2009 Camry 4-cylinder emission tested as required to get updated plate tags in Arizona. I failed the test with a DTC code of P2237. Apparently this code indicates that the upstream oxygen sensor is reading out of spec.
Here's my question - should my check engine light have lit up for a P2237 code ?
At no time did my check engine light illuminate and it still doesn't. I know its functioning correctly as it goes on when the ignition is turned on and when starting the engine it lights for a couple seconds and then turns off as normal. The emissions test even passed the car for the "CEL light functioning normal" portion of the test.
With 90K miles I understand that I need to replace my upstream oxygen sensor (easy job), but my concern is if the check engine light didn't come on do I have a bigger problem ? Or does the CEL not light up for the P2237 code ?
Thanks in advance for any help anyone can offer.
Jerry

 

check the wires and connector to that 02 sensor

if that is ok


replace the 02 sensor ....they dont last forever