O2 codes need serious help
Thread Starter
Racer
Joined: Mar 2007
Posts: 323
Likes: 0
From: Austin Texas
O2 codes need serious help
so i got a 2000 vet just did a motor swap to a ls3.. before i did the swap i was getting codes for o2 sensor heater circut bank 1 sensor 1 and bank 2 sensor 1, also bank 2 sensor 1 no activity.. i figured it just needed new sensors.. i do the motor swap change out o2 sensors and flash computer and they come back so i see that the harnesses got a little melted on the lt's so i replace the harnesess wrap them in heat wrap and make sure they dont hit the exghaust,, they come back again,, i check all the fusess and find a blown on 10amp in the floor board box and the car starts running better but still these three codes keep coming back.. what tha heck ,, i have also checked all the grounds on the frame under the hood and gone so far as to add extra groung straps to all of them off of the body of the altenator and the batt even one directly to the LT's from the engine block,, im loosing my mind trying to figure this out.. its pull the motor out and check every square inch of the wires or replace the computer,, please does some one else have any idea of what could be going on???
Melting Slicks
Joined: Oct 2007
Posts: 2,383
Likes: 13
From: Kinston North Carolina
You might already have this schematic, if not, you need it.
Which fuse did you replace in the IP Fuse Block?
----------------------------------------------
Which fuse did you replace in the IP Fuse Block?
----------------------------------------------
Last edited by byronhunter; Jun 11, 2010 at 11:40 PM.
Thread Starter
Racer
Joined: Mar 2007
Posts: 323
Likes: 0
From: Austin Texas
Tech Contributor
Joined: Jan 2007
Posts: 19,353
Likes: 1,125
From: Dyer, IN
Ok. Monitored LD is for lighting, and has nothing to do with the O2's. Byronhunter has provided you with a schematic, and you can see that the fuse for the heaters is minifuse # 15 in the underhood fuse box....so that needs to be checked. If you have an inactivity code, and you have a melted harness, then you need to inspect the wiring for shorts/opens. You can also disconnect PCM connector C1, and read the O2 sensor(s) wire resistance, and check for shorting to ground, and each other.
Thread Starter
Racer
Joined: Mar 2007
Posts: 323
Likes: 0
From: Austin Texas
Ok. Monitored LD is for lighting, and has nothing to do with the O2's. Byronhunter has provided you with a schematic, and you can see that the fuse for the heaters is minifuse # 15 in the underhood fuse box....so that needs to be checked. If you have an inactivity code, and you have a melted harness, then you need to inspect the wiring for shorts/opens. You can also disconnect PCM connector C1, and read the O2 sensor(s) wire resistance, and check for shorting to ground, and each other.
Tech Contributor
Joined: Jan 2007
Posts: 19,353
Likes: 1,125
From: Dyer, IN
Possible....yes....probable....no.
Since you did have damaged wiring, I would approach in the following way:
1) If fuse #15 is good, then check for 12 volts at each O2 harness connector at pin D, brown wire(s)....ignition must be in "on" position for this test.
2) At the same connector(s), check the resistance to ground at pin C, black wire(s).
For the inactivity issue, you'll need to evaluate the sensor wiring between the PCM and O2 connector(s) at the harness. Disconnecting PCM connector C1, and reading the resistance to ground of each individual wire from the PCM connector to the appropriate O2 sensor connector. Also check for shorting by checking the resistance between the wires themselves, and finally continuity of each wire. All these tests must be done with the PCM connector, and O2 sensors disconnected.
Note, this will only evaluate the O2 harness.
Since you did have damaged wiring, I would approach in the following way:
1) If fuse #15 is good, then check for 12 volts at each O2 harness connector at pin D, brown wire(s)....ignition must be in "on" position for this test.
2) At the same connector(s), check the resistance to ground at pin C, black wire(s).
For the inactivity issue, you'll need to evaluate the sensor wiring between the PCM and O2 connector(s) at the harness. Disconnecting PCM connector C1, and reading the resistance to ground of each individual wire from the PCM connector to the appropriate O2 sensor connector. Also check for shorting by checking the resistance between the wires themselves, and finally continuity of each wire. All these tests must be done with the PCM connector, and O2 sensors disconnected.
Note, this will only evaluate the O2 harness.
Last edited by lucky131969; Jun 12, 2010 at 02:41 PM.
Thread Starter
Racer
Joined: Mar 2007
Posts: 323
Likes: 0
From: Austin Texas
Possible....yes....probable....no.
Since you did have damaged wiring, I would approach in the following way:
1) If fuse #15 is good, then check for 12 volts at each O2 harness connector at pin D, brown wire(s)....ignition must be in "on" position for this test.
2) At the same connector(s), check the resistance to ground at pin C, black wire(s).
For the inactivity issue, you'll need to evaluate the sensor wiring between the PCM and O2 connector(s) at the harness. Disconnecting PCM connector C1, and reading the resistance to ground of each individual wire from the PCM connector to the appropriate O2 sensor connector. Also check for shorting by checking the resistance between the wires themselves, and finally continuity of each wire. All these tests must be done with the PCM connector, and O2 sensors disconnected.
Note, this will only evaluate the O2 harness.
Since you did have damaged wiring, I would approach in the following way:
1) If fuse #15 is good, then check for 12 volts at each O2 harness connector at pin D, brown wire(s)....ignition must be in "on" position for this test.
2) At the same connector(s), check the resistance to ground at pin C, black wire(s).
For the inactivity issue, you'll need to evaluate the sensor wiring between the PCM and O2 connector(s) at the harness. Disconnecting PCM connector C1, and reading the resistance to ground of each individual wire from the PCM connector to the appropriate O2 sensor connector. Also check for shorting by checking the resistance between the wires themselves, and finally continuity of each wire. All these tests must be done with the PCM connector, and O2 sensors disconnected.
Note, this will only evaluate the O2 harness.
Tech Contributor
Joined: Jan 2007
Posts: 19,353
Likes: 1,125
From: Dyer, IN
OK OK... sorry its been a few days ive been out of pocket.. just started testing the harness at the o2's i got 12v on the brown but i dont have ground on the black.. ive checked my engine grounds they are all hooked up.. should i cut the black wires and just run them to ground.. would that be ok?
That would not be my approach, because the wiring is already in place, so you need to investigate where the open is. You've gone to the trouble to do an engine swap, don't start rigging up stuff now. Hard to believe all the grounds are bad at the splice pack, unless some creative wiring was done in this motor swap.
Hopefully you are checking each connector v/s a known good ground. If you are confident this is the case, then SP122 is the common connection point. If the oil level and fuel pump relay are working, you at least know the ground from G105 to SP122 is good......so you'll have to figure out what the problem is.
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Thread Starter
Racer
Joined: Mar 2007
Posts: 323
Likes: 0
From: Austin Texas
That would not be my approach, because the wiring is already in place, so you need to investigate where the open is. You've gone to the trouble to do an engine swap, don't start rigging up stuff now. Hard to believe all the grounds are bad at the splice pack, unless some creative wiring was done in this motor swap.
Hopefully you are checking each connector v/s a known good ground. If you are confident this is the case, then SP122 is the common connection point. If the oil level and fuel pump relay are working, you at least know the ground from G105 to SP122 is good......so you'll have to figure out what the problem is.
Hopefully you are checking each connector v/s a known good ground. If you are confident this is the case, then SP122 is the common connection point. If the oil level and fuel pump relay are working, you at least know the ground from G105 to SP122 is good......so you'll have to figure out what the problem is.
Tech Contributor
Joined: Jan 2007
Posts: 19,353
Likes: 1,125
From: Dyer, IN
That being the case, you most likely left off (or damaged) one of the ring terminals at engine ground G105(as below). One is the ground strap to the frame, and the other is a ground for SP122, which provides a ground for the fuel pump relay, oil level sensor, and O2's. Stop bypassing things that don't work, and fix the problem.
http://forums.corvetteforum.com/c5-t...e-grounds.html
Thread Starter
Racer
Joined: Mar 2007
Posts: 323
Likes: 0
From: Austin Texas
You don't say?
That being the case, you most likely left off (or damaged) one of the ring terminals at engine ground G105(as below). One is the ground strap to the frame, and the other is a ground for SP122, which provides a ground for the fuel pump relay, oil level sensor, and O2's. Stop bypassing things that don't work, and fix the problem.
http://forums.corvetteforum.com/c5-t...e-grounds.html
That being the case, you most likely left off (or damaged) one of the ring terminals at engine ground G105(as below). One is the ground strap to the frame, and the other is a ground for SP122, which provides a ground for the fuel pump relay, oil level sensor, and O2's. Stop bypassing things that don't work, and fix the problem.
http://forums.corvetteforum.com/c5-t...e-grounds.html
Tech Contributor
Joined: Jan 2007
Posts: 19,353
Likes: 1,125
From: Dyer, IN
I'm not suggesting, in any way, that you pull the motor to resolve this issue. The reason why your fuel pump, oil level, and O2 heaters are not operating correctly is due to a ground issue..specifically..lack of ground. All the aforementioned are connected to SP122, which is located under the battery tray. SP122 is grounded at G105. Fix the ground, and fix ALL the issues.
Good luck.
Thread Starter
Racer
Joined: Mar 2007
Posts: 323
Likes: 0
From: Austin Texas
Perhaps you are not understanding me, or cannot read the schematics....or have not read the info I have posted....so I'll leave you with this.
I'm not suggesting, in any way, that you pull the motor to resolve this issue. The reason why your fuel pump, oil level, and O2 heaters are not operating correctly is due to a ground issue..specifically..lack of ground. All the aforementioned are connected to SP122, which is located under the battery tray. SP122 is grounded at G105. Fix the ground, and fix ALL the issues.
Good luck.
I'm not suggesting, in any way, that you pull the motor to resolve this issue. The reason why your fuel pump, oil level, and O2 heaters are not operating correctly is due to a ground issue..specifically..lack of ground. All the aforementioned are connected to SP122, which is located under the battery tray. SP122 is grounded at G105. Fix the ground, and fix ALL the issues.
Good luck.
