anybody know which fuse supplies power for the 5V reference signal for O2 sensors?

dhrmx5

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Idiot clutch installer managed to cut a set of O2 sensor wires when he clamped them in between the trans and block. They are repaired but car now breaks up between 2500 and 4000 rpm. I need to find the fuse that provides the power for the 5V reference signal for the sensors. Anybody know?
 

redfirepearlgt

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It may be F1.45 in the BEC which is a 10A. Or it could also be F1.47 in the BEC which is a 15 A.

F1.45 is hot at all times so if the person pinched the wires against the block that may have blown your fuse. However that is just the source for the heaters.

Pin 3 on all four connectors is the signal source from the PCM
Pin 4 on all four connectors is the signal return from the O2's back to the PCM via a common splice S102.

You will need a multimeter to check. A test light will not perform this function. As mentioned this is a 5v signal voltage source.

That said if he is that unobservant then it is possible your problem is another case of cable swap as some recently learned on here. Data from bank 1 O2 is seen as bank 2 data by the pcm and vice versa and the STFT's and LTFTs go crazy. At some point you get rich and/or lean codes popping up. Not saying this is your problem but it easily happens on 05-09's because of how the harness lays out.

Connector C172 pin 3 wire is Red/Black stripe. Should be on lead O2 sensor 2 (bank2 drivers side)
Connector C171 pin 3 wire is Gray/LightBlue stripe. Should be on lead O2 sensor 1 (bank 1 passenger side)
Connector C141 pin 3 wire is Violet/Light Green stripe. aft O2 sensor 2 bank 2
Connector C142 pin 3 wire Red/Light green stripe. aft O2 sensor 1 bank 1
 

dhrmx5

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Redfire for the win. I fixed it yesterday as I re-examined the fuses and found #47 was blown, just not in an easily seen fashion. Replaced it and car is fine.
Came back on here to see if there were any answers and Redire has it on his answer. Thanks for the assistance.
 

redfirepearlgt

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glad it was that simple. surprised there werent other codes popping up with that fuse blown.

appreciate the feedback. this helps others using the search function that may have the same issue in the future.
 

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