Mike Sigmond

Green??? Yea I would try GM, they might not know details that deep, but its worth a try.

Mike Sigmond

I will look at mine today so we can compare apples to apples if GM isnt any help, thats a pretty deep technical question for the average parts guy or tech.

516rider

yea i just got off the phone with them. they said to bring it by to look at. they didnt know what the gauge was or does. i told them the wires i have and current. so im just gonna wait a lil longer.

Mike Sigmond

I figured, they just want $$. I will hook my toner up to the o2 wires and trace them back to the computer, It might be a day or so until I can get to it, I am with my kids during the week. I did take a pic of my after cat sensor wires but I want to post all of them.

Here is the pic I took , the wire colors change to red ,white etc.. after the plug, I really need to tone them to see where they go. also attached is a schematic for your truck, not a generic one. It only shows power feeds not signals. Pink is power for the heater thats for sure.

516rider

wow thats amazing. thank you sooo much. i can wait as long as it takes. im in no hurry to hook it up.

Mike Sigmond

Not a problem at all, like I said, Iam learning them too as we go along. If you want all the schematics for your truck let me know, Ill post them. My reason for studying the sensors is to know when they are bad, you cant tell if a sensor is bad by looking at it, you have to see the voltages to see if they are out of range, a good shop manual will give you the normal operating voltage ranges.

Here is another tip about them:
The oxygen sensor in front of the catalytic converter normally has a fluctuating waveform (voltage). The waveform(voltage) of the sensor behind the converter should be more steady

Mike Sigmond

Ok , I found your ECM & PCM diagrams, I posted all your power dist diagrams too the rest are in the next post. I see your green wire too, it all makes sense to me now.

Mike Sigmond

And the rest of the PD's. I hope this helps. Ill still look at mine and take some pics when I can. Let me know if you need any help reading the schmatics. you can print them and set them next to each other to route where they go. Looks like the ground is provided off the exaust pipe, you have signals o2 hi & o2 low that go the ECM and the heater control goes to the PCM, thats the next thing I need to figure out. I think the PCM shuts off the heater in the o2 after temp is reached. A volt meter will answer that for me once I get a chance.

516rider

ok i will look at them once i get a chance. hopefully this will help

516rider

ok sorry it has been a while since i was on. ive been racing for the last few weeks and graduation from high school. well before i got a chance to look at it. i got an 04 duramax. so i have no need for the gauge. instead i went and got a boost gauge.