connection to the tcm/tcu on a 2006 traiblazer ss

[bstuder11]

I seem to have no to way to look at the trasmission control module at all with my efi live and I am having serioius shifting issues with the 4l70e thats in it. I went with EFI live years ago because it was supposed to be better than hp tunner. I found a friend that says he tunes the tcm in these trailblazers all the time and he is using HP tuners :confused: So my question is am I overlooking a way to get into the tcm with efi live or am I gonna have to haul the truck over an hour away to my buddy with hp tunner???

[joecar]

If your V7/V8 software and V2 firmware is up to date you should be able to edit/tune T42/T43.

[bstuder11]

Yeah thanks so much for the help, I have never had to switch controllers like this before but I had a good friend that got me into tuning call me right before i read your reply and he said the same thing. Now I just hope I can get some helpful info off of it so I know how to proceed with repairing the truck.

[joecar]

What is your V2 firmware version...?

What are the build versions of your installed V7 and V8 software...?

[bstuder11]

Ya know, il not sure what the firmware is I know I just did an update like a month ago though. Anyways I was able to get into the TCM and its saying solenoid D is bad. Anyone know which one that is?

[ScarabEpic22]

Its the same in all 4L60/65/70Es but I dont know which one it is. Its probably easier to replace both and maybe the wiring harness when you drop the pan, I think the solenoids arent that expensive.

[joecar]

Solenoid D would be inside the 6L80/6L90... you will need the Service Manual.

[bstuder11]

I wish I had a 6L something lol but no this is a 4L70 in my 2006 trailblazer SS. I know there are inside and I have replaced them in 4l60's and 65's but they are identical so it's hard to know which one it is. Ill probably just change em both.

[joecar]

Then it's sol A or B, like Erik said, they look identical and are cheap enough to replace both.

[bstuder11]

I noticed something else while watching my data just now also. Only first and second gears show up in the data. It shows them correctly on the dash but in efi live its like the computer isn't seeing me shift into 3rd or 4th. Any ideas on that one?

[joecar]

Post your log file.

[bstuder11]

Man I didn't save it and I have just finished pulling the tranny pan, checking the resistance on the shift solenoids (both at 23). The pan fluid ect. Was dirtier than I thought it was so I'm glad I opened it up just don't wanna spend the 8 bucks a quart for the fluid lol. On a serious note though it kinda would make sense it wanting to stay in first when that's what the computer is seeing and there was a couple mornings even the dash was reading 1st gear when I started it but I didn't really think much of it at the time cause it would go away after it warmed up. I'm not sure if that means the shift indicator on the side of the tranny is bad or what.

[bstuder11]

Ok so after a few more hours of inspecting, cleaning, and watching videos I found that the pressure manifold switch (have had to replace many of these over the years and gm did away with after 08) is what tells the computer what gear its in so Im about 90% sure after I replace this and replace the fluid with new it should fix it...fingers crossed. Thanks very much for your input, time, and trying to help me through this!

[joecar]

Let us know how you go.

[bstuder11]

I definitely will, I'm going to see if any of the parts stores stock the manifold pressure switch and if so buy new fluid and filter and then ill let y'all know how it went. Again, thanks so much for the help!