p0157
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Joined: Dec 2006
Posts: 55
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From: concord ca
p0157
engine light and code p0157. I switched ox. sensors left to right and still get p0157 code whitch is pass rear ox sensor. Its good in morning but in the afternoon it trips. Any suggestions?
Tech Contributor
Joined: Dec 1999
Posts: 32,910
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From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
There are LOTs of things other than the O2 sensor that can cause the DTCs to set. You need to inspect the wiring harnesses and ALL the connetcors. The connectors need to be inspected very closely. Look for corrosion and also look for poor connections. The female pins in all of GMs connectors are suspect for fatuge and over time, they loose their tension and cause poor connection. I use a spare male pin to test EACH female pin in any circuit that Im having issues with.
Then there are the GROUND connections. All C5 circuits have ground wiring paths. So do your O2 sensors. The ground wires terminate in splice packs and they go directly to chassis ground. The splice pack for the O2 sensors is under the battery and it has been known to be exposed to battery acis and look like this:
Check your splice pack.
BC
Then there are the GROUND connections. All C5 circuits have ground wiring paths. So do your O2 sensors. The ground wires terminate in splice packs and they go directly to chassis ground. The splice pack for the O2 sensors is under the battery and it has been known to be exposed to battery acis and look like this:
Check your splice pack.
BC
Thread Starter
Advanced
Joined: Dec 2006
Posts: 55
Likes: 0
From: concord ca
02 senser
There are LOTs of things other than the O2 sensor that can cause the DTCs to set. You need to inspect the wiring harnesses and ALL the connetcors. The connectors need to be inspected very closely. Look for corrosion and also look for poor connections. The female pins in all of GMs connectors are suspect for fatuge and over time, they loose their tension and cause poor connection. I use a spare male pin to test EACH female pin in any circuit that Im having issues with.
Then there are the GROUND connections. All C5 circuits have ground wiring paths. So do your O2 sensors. The ground wires terminate in splice packs and they go directly to chassis ground. The splice pack for the O2 sensors is under the battery and it has been known to be exposed to battery acis and look like this:
Check your splice pack.
BC
Then there are the GROUND connections. All C5 circuits have ground wiring paths. So do your O2 sensors. The ground wires terminate in splice packs and they go directly to chassis ground. The splice pack for the O2 sensors is under the battery and it has been known to be exposed to battery acis and look like this:
Check your splice pack.
BC
