2006 tbss 4l80e

I just picked up a 2006 TBSS, which has always been a dream to own, that had a few thrown rods. I swapped my 408/4l80E into it and came across the issue where the VSS wouldn't populate in the scanner and the cluster showed it was in 1st gear the entire time. I didn't do any prior research because I have segment swapped dozens of vehicles without issue. When the issue happened, I got on here and a few other forums and saw that this was a super common issue with a few work arounds including the PCMofNC and LC32 options (which both seem great and reliable) but I love a good challenge of figuring something out. I built my own harness, modified the stock crossmember, and used the stock driveshaft with a new yoke. The driveshaft could actually be a little longer IMO. I just wanted to share my tune for anyone else that is a DIYer. The tune isn't finalized, and I need to adjust some shift points, but it runs and drives and everything works like stock. I have a Huron Speed kit on the way, so it has stock manifolds and y-pipe (because who uses that on a 408 haha).

Attachment 128157Attachment 128158Attachment 128159Attachment 128160

Good job! Thanks for sharing.

Did you do a write-entire on the TCM with another file, or segment swap? And which combo initially had it with the PRNDL/VSS not working?

I looked at the file last night and compared it to stock, and '07 Suburban (the one commonly recommended, with the same TCM OS) and couldn't figure out exactly which bits of which one got used in the end.

OK, been digging some... your working file has these segments:

24235341 Operating System
24232586 Transmission
24238958 Diagnostic
24233116 System

The common reference file of the '07 Suburban has:

24235341 Operating System
24233118 Transmission
24238957 Diagnostic
24233116 System

Looking through your changelog you started out with the stock TBSS segments of:

24235341
24232586
24237702
24232583

...then tried the Suburban segments (complete file write-entired, or segment swapped?), then after only like 4-5 revisions that 24238958 segment appears.

Now this old file I found somewhere is also an '06 TBSS 4L80 with everything apparently working, without relay harness or other tomfoolery. It has the same Diagnostic segment you used, and I can't find that segment in any of the other reference files I have. Where'd it come from?!

Attachment 128196

p.s. I'm only being so obsessive about this because I also have one of these trucks and when the 60E bomb finally goes off it too is getting a 4L80...

Intarwebs sleuthing brings up mentions of an '07 Yukon. VIN 1GKGK26K47R153097. Which decodes to a 4WD Yukon XL 2500. I really, really want that stock file.

So I segment swapped the three HPTuners gives the option of and did a write entire. That’s when I had the issues as well as the U code saying that it lost communication with TCM/PCM. From there I noticed in the 07 tune that the TUTD is set to serial and D3 whereas the TBSS (not having TUTD as an option at all) is set to hardwired and P to activate.

I’m unsure of where the unknown diagnostic segment came from now that you mention it. I only used my file and one from the repository (2007 Suburban). I’m wondering if one of the changes I/we made in the trans segments changes the segment number to that when complete.

Changing settings in the tune only changes the CVN hash. The only way to make only one of the the Cal IDs change is a segment swap.

A post at another forum listed a 2007 Yukon with the same 4 trans segments as you and my old file used, but I haven't been able to find an actual file. And TIS is down with a 'database error' so I can't run the VIN to confirm those Cal IDs. Of course, I or anybody else can use the already-swapped files as a source for the magical 24238958 segment, but I'd just like to have the stock file it came from. (autism! yay!)

So I did some digging in my folder of making that tune and remembered that I did pull a file from a thread that had that diagnostic ID in it. I did this entire swap in one day and tried multiple things so it all kind of ran together. When I get home tonight, I’ll upload that file I pulled from the forum, but it’s what’s in my tune as you figured out! I have about 9 different tunes in the folder from trying to get this figured out!

Why are the trailblazers such a pain in the ass? Everyone I've talked to says 'oh, an 4l80 swap is easy!'

Tried the repin/segment swap & was running into similar issues. Gave up, bought the Pcmof Nc harness, put the pins back to stock & still having issues. The 1-2 shift solenoid is staying energized all the time with or without the harness

PCM of NC plug instructions specifically state not to make OS changes or copy anything from a 4l80e TCM OS.

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Originally Posted by spent21

Why are the trailblazers such a pain in the ass? Everyone I've talked to says 'oh, an 4l80 swap is easy!'

Tried the repin/segment swap & was running into similar issues. Gave up, bought the Pcmof Nc harness, put the pins back to stock & still having issues. The 1-2 shift solenoid is staying energized all the time with or without the harness

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Have you reached out to us? Send a email with your current tune file and a note describing the issue to [email protected]

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Originally Posted by eXo3901

PCM of NC plug instructions specifically state not to make OS changes or copy anything from a 4l80e TCM OS.

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And yet we deal weekly with guys who can't get them running because they also did a OS or segment swap. It's literally re-tune for different gear ratios, turn off a diagnostic or two depending on application and roll

I was going to say that it seems like you did the swap harness and the 80e segment together and it’s interfering. They have the best reputation for making these work easily and reliably, so I’m sure they will get you fixed up!

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Originally Posted by Alvin

Have you reached out to us? Send a email with your current tune file and a note describing the issue to [email protected]

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i've been holding off because I want to verify my pin positions before causing a stir.

to clarify, I repined, segment swaped, & had issues.
repin back to stock configuration, Loaded previous 4l60 tune, followed included instructions.

I may have a wiring issue as my 1-2 solenoid is energized all the time with or without the conversion harness. Since the Tcu controls solenoids by controlling the grounds, I may have a pinched/grounded wire. I want to verify my wiring & tune before I start pulling you guys into the mix.

My frustration comes not from Pcm but that the Tbss in particular seems to be a mix bag that deviates by year from Silverados for instance.

Have you verified at the trans plug that the pcm is sending the ground signal to energize the shift solenoid? What are your symptoms?

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Originally Posted by simman22

Have you verified at the trans plug that the pcm is sending the ground signal to energize the shift solenoid? What are your symptoms?

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I pulled the pan, unplugged 1-2 & 2-3 shift solenoids. I'm testing voltage across the plugs for each. 2-3 will cycle off/on as it should. 1-2 is constant on.

The 1-2 will be on in park, reverse, neutral, and drive (1st) and so on. What happens when you drive it? Have you ran it on jackstands to circulate fluid through the trans and valve body so valves and pressure switches function? What are the driving symptoms that you are fighting? That might be easier to diagnose.

I just wanted to update that this will also work on a 2007. You'll have to just write entire the trans. I assumed it wouldnt, so I tried the Suburban file (had issues) then flashed this one in, and all is good, including the PRNDL.

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Originally Posted by simman22

I just wanted to update that this will also work on a 2007. You'll have to just write entire the trans. I assumed it wouldnt, so I tried the Suburban file (had issues) then flashed this one in, and all is good, including the PRNDL.

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I did everything you listed 2006 TBSS and so far my only issue is the indicator stays in P. The trans shifts and doesn't throw codes. Im having PCM of NC do remote tuning for me so I can change anything yet. I can ask them to make adjustments when I email the logs for tune updates. Your advice and tune are much appreciated!

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Originally Posted by simman22

The 1-2 will be on in park, reverse, neutral, and drive (1st) and so on. What happens when you drive it? Have you ran it on jackstands to circulate fluid through the trans and valve body so valves and pressure switches function? What are the driving symptoms that you are fighting? That might be easier to diagnose.

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I had the intercooler leak & hydrolocked the engine, so haven't really done much until recently.

The trans has a Ck "recalibration" shift kit which has an accumulator delete & also mods to dual feed the direct clutch all the time.

https://www.ckperformance.com/View/4...ATION-KIT-LATE
https://www.ckperformance.com/files/...UCTIONS%20.pdf

This trans should bark the tires, but I have soft shifts & prolonged 2-3 when in drive & feels like it may be slipping. If i put it in 3, the shifts firm up. I'll get some logs in a week or 2.