What did you do to your NNBS GMT900 Tahoe/Yukon Today?

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Doubeleive

Wes
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anybody know off hand if I grab a spare ecm and program it to the truck can I then swap the 2 at will? like plug-n-play or will I have to re-program them each time?
just wondering if the security relearn would need to be done each time or not
reason being there rather cheap as low as $55 and mine is BB tuned and cali has this stupid new "tune" check for smog/registration. Then i could swap it for the smog and stick it on a shelf for next time.
 

iamdub

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anybody know off hand if I grab a spare ecm and program it to the truck can I then swap the 2 at will? like plug-n-play or will I have to re-program them each time?
just wondering if the security relearn would need to be done each time or not
reason being there rather cheap as low as $55 and mine is BB tuned and cali has this stupid new "tune" check for smog/registration. Then i could swap it for the smog and stick it on a shelf for next time.

Pretty sure you can since you can have a tuner program another PCM while you keep your stock one, then just swap it when it arrives. I don't know about the security re-learn, but most tuners disable VATS as standard procedure. There may be some sort of learning thing required, but I'd imagine that once it's learned, both PCMs will be good to go.

I could be wrong, though.
 

wsteele

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anybody know off hand if I grab a spare ecm and program it to the truck can I then swap the 2 at will? like plug-n-play or will I have to re-program them each time?
just wondering if the security relearn would need to be done each time or not
reason being there rather cheap as low as $55 and mine is BB tuned and cali has this stupid new "tune" check for smog/registration. Then i could swap it for the smog and stick it on a shelf for next time.
I don’t think the “system” has a way of knowing, as long as all the subordinate systems are all in synch.

As Chris mentioned, I can take my ECU out, send it to a tuner, have AFM turned off and reflashed and install it without any other issues.

Maybe just reflash the stock image for the smog test?
 

Doubeleive

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I don’t think the “system” has a way of knowing, as long as all the subordinate systems are all in synch.

As Chris mentioned, I can take my ECU out, send it to a tuner, have AFM turned off and reflashed and install it without any other issues.

Maybe just reflash the stock image for the smog test?
I already have the ecm on the way and I do not have a stock image, I had a hypertech on it and had the transmission worked on and when they replaced the tcm the hypertech no longer works and thinks the system has been overwritten and hypertech wants $200 to unlock the tuner, so my stock file is a hybrid, I should have put it back to stock before having the transmission worked on but o'well. so when the ecm gets here I will use the tech2 and relearn it to my vin and see what happens when I swap the original back I in I guess.
 

wsteele

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I already have the ecm on the way and I do not have a stock image, I had a hypertech on it and had the transmission worked on and when they replaced the tcm the hypertech no longer works and thinks the system has been overwritten and hypertech wants $200 to unlock the tuner, so my stock file is a hybrid, I should have put it back to stock before having the transmission worked on but o'well. so when the ecm gets here I will use the tech2 and relearn it to my vin and see what happens when I swap the original back I in I guess.
Got it. Have you ever used the pass through stuff on the Tech 2? I haven’t bothered to dig my old laptop out and get that stuff working.

I wonder if there is anything published by Cali on what they actually are going to compare when they perform the test?
 

Fless

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I already have the ecm on the way and I do not have a stock image, I had a hypertech on it and had the transmission worked on and when they replaced the tcm the hypertech no longer works and thinks the system has been overwritten and hypertech wants $200 to unlock the tuner, so my stock file is a hybrid, I should have put it back to stock before having the transmission worked on but o'well. so when the ecm gets here I will use the tech2 and relearn it to my vin and see what happens when I swap the original back I in I guess.

Following. I have heard that it works this way for both NBS and NNB, being able to simply swap the ecm. Next time I'm at upull I'm going to pick up a spare ecm and try it on my NBS. Curious about the Theftlock learning; not sure it's in the ecm.
 

alpha_omega

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For the last few days I get the ABS and traction faults every now and then on startup. Goes away at the next start or later in the day. I’ve scanned it twice and it’s the LR wheel speed sensor circuit C0045_00. Cleaning the connector at the wiring harness had no effect.

Any realistic chance it’s anything other than the sensor? I’ve got an OEM sensor in my shopping cart ready to pull the trigger.
Not saying your diagnosis of the wheel speed sensor isn’t correct, but have you also checked out the grounds and the brake light switch located at the brake pedal? These two are the main culprits when dealing with phantom ABS and traction control lights.

Also, while these TSB’s and similar ones may not be for your specific year, their problems often carry over to previous and later year models.



Another TSB is PI0639C. I have the print out handy but not the link. It’s related to the “service stabilitrak” message and the fix is to use a very small amount of dialectic grease (too much can cause hydrolock) and using some adhesive stock (Kent Automotive P40100) as a shim under the steering wheel position sensor.
 
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alpha_omega

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Has anyone any experience with GM’s warranty on parts? Two months ago I had a dealer on the east coast replace a window regulator RF door. Now that I’m on the opposite side of the country it’s dragging and needs help to close, just like before.

Just wondering what the response will be when I take this to a dealer out here and request a warranty fix on that window?
I wonder if they just forgot to tighten things down inside there. I’ve seen that happen where new parts were thrown at it, but the only thing needed was a little more UMPHH on a bolt/screw.
 

alpha_omega

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Where I take my Yukon year round means I never get it totally clean underneath. I pressure wash it occasionally and always use the car wash that has a double undercarriage spray setup.

When I recently did my O2 sensors, it was like walking into a sandstorm. I started with safety glasses and ended up with monogoggles over them. You think you can reach up and not rub anything causing the shower of sand...
I feel your pain!

I’m guessing it looks something like this. With goggles on I still didn’t dare open my eyes until after I wiped my face off. It may not look like much, but remember I was lying on that creeper, which means I was wearing whatever rust, dirt and debris is not on the cardboard or the creeper. That was after taking it through the wash, using my air wand and shop vac…the one spot I missed was the mounting location for the front sway bar bolts.

5B4C8E71-3376-446D-87E9-9D41062F8463.jpeg
 

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