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PO151 PO432

1K views 5 replies 3 participants last post by  43sqd 
#1 ·
Pulled these codes yesterday. Catalytic converter was replaced a couple weeks ago. 151 is showing low voltage bank 2, position 1 02 sensor. 452 shows converter is operating below specs. I'm suspecting he either damaged the O2 sensor while performing the repair OR he has left me with an exhaust leak from an improper weld. Any input is appreciated.
 
#3 ·
i wouold suggest you check the connections under the truck for corrosion. If you have ever had a leak from a blocked channel or a wet spot on the floor of the passenger side you probably have corrosion on the contacts. I have seen them so bad that a new socket had to be installed. talk to your indie and see what he observed when he replaced the O2 sensor. Chances are he didn't pay particular attention to the socket. you need to check voltage WITHIN THE SOCKET. Meaning your positive and negative must come from within the socket not a positive from the socket and negative from the chassis. Good Luck.
 
#6 ·
Clint, both codes are for the left side, the CAT and the left O2 sensor before the CAT.

I would concentrate on the P0151 code which shows that there is a short in the signal wire of that sensor, which could be two possibilities.

The signal wire (O2 sen. harness) could have touched the exhaust system somewhere triggering the code, or for some reason it became severed. So the 4 wire harness must be thoroughly inspected.

As for the CAT code P0432, I would wait until the O2 sensor problem is resolved as it might be affecting its readings.
 

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