So these two DTCs are saying that the voltage for the Ho2 sensor stayed high after start up for too long based on the ECT and amount of air. They are not saying that the converter is not efficient.
I attached the tests for this to determine what the root cause is. The difference between these tests are if you have an isolated ground for the o2 or they are case grounded. Meaning to you have a ground wire coming from the sensor or not. Obviously you will need to follow the test for whichever you have.
It looks like based on the test that it most likely is a wiring issue or a PCM. Clearly going through the test will tell you what needs to be fixed.
Let me know if you need anything else and I will assist how I can. Thanks
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Monday, June 10th, 2019 AT 2:44 PM