Codes P2a00 and p1172

2006 HONDA CRV
158,000 MILES • 4 CYL • 4WD • AUTOMATIC
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STRATTON.M23
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The check engine light is on and the coded read p2a00 and p1172. I have read online that this can indicate the upstream sensor is failing. Is this correct? It also says a software update is required, is this also correct?
Apr 2, 2021 at 8:46 AM
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STRAILER
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Yes, it sounds like the primary oxygen sensor has failed. Here is a guide to help you step by step with instructions in the diagrams below to show you how on your car:

https://www.2carpros.com/articles/how-to-replace-an-oxygen-sensor

Check out the diagrams (below). Let us know what happens and please upload pictures or videos of the problem.
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Apr 3, 2021 at 11:10 AM
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STRATTON.M23
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Have you heard of needing a software update on the CRV to fix this problem? I read it needs to be done before changing the sensor or the sensor will end up failing.
Apr 3, 2021 at 3:21 PM
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STRAILER
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I have not heard of this, but it could be true. the only way is to have an update done and then change the sensor.
Apr 4, 2021 at 9:45 AM
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STRATTON.M23
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I have to order the upstream sensor but the online is recommending ordering the downstream as well. Do I need to replace both if only the upstream is sending the code?
Apr 4, 2021 at 9:49 AM
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STRAILER
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I would just do the upstream sensor first to see what happens.
Apr 4, 2021 at 9:57 AM