Replace front o2 sensor procedure - Very Easy or Easy? (1 Viewer)

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Mine just threw the same codes...What did you end up finding out? Thanks, Mike



I need some help deciphering my CEL reader. My truck just threw the P0155 code which means the Bank 2/Sensor 1 O2 sensor needs replaced.

The CEL reader displays as follows:

Fault P0155
01/02

and

Pending Fault P0155
02/02

My question is what does the 01/02 and 02/02 mean and what is a pending fault? Thanks in advance...
 
Anyone have feedback on the above mentioned post? Thanks much!
 
My guess is it is telling you you have triggered two codes. First you had a pending fault code and then the same code turned into a hard fault code. They are listed in chonalogical order with the most recent one first. Hence, the pending code is shown as #2 of 2 and the more recent hard code is shown as #1 of 2. They are both the same issue.
 
My first check engine light since purchasing from original owner in 2018 at 188k miles, a good 5 years later.

I did have one check engine light early in the purchase, but I replaced gas cap and never again came back, in hindsight might have actually been related to these old o2 sensors, who knows!

replaced both o2 upstream sensors, those damn tabs were the worst took me a good hour of trying all angles and using flat head screw driver but I finally got both out, the o2 sensors were hand tight I was able to just use my hands to unscrew, have to love California rigs.

Let's hope that's my last check engine light for another 5 years.
 
replaced both upstream o2 sensors proactively after getting a fault code for bank 1 sensor 2 downstream sensor p0037 (replaced this one too). the sensors were likely original and looked pretty tired.

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