4L60E Scan Shift Solenoid Question

[freygreer]

Hello, I am a little confused with what my scan is telling me. I have the Corvette service manual and it says that in 1st gear I should see (1-2 Shift Solenoid on and 2-3 Shift Solenoid on) which is correct in my scan. But when the car is in 2nd the scan shows (1-2 shift solenoid on and the 2-3 shift solenoid off) which is opposite from the service manual. In third gear, the scan matches the service manual (off, off) but in 4th gear again the scan is opposite from the manual (Scan off, on) and (manual on, off).

The troubleshooting in the service manual says that it should match so I am really confused and any help would be appreciated.

[Hutchinson]

This is exactly the issue I'm currently having (please see my other posts on 4L60e's). Have you swapped PCM's or done any other work to your Vette (so we can compare notes)? Have you put a pressure gauge on the test port (driver's side above shift lever) to see what your line pressures are?

Let's compare notes here bud, maybe we can help each other out.

[Hutchinson]

Hey Freygreer, did you ever figure this out/get it sorted? If so, what was it bud?

I've the same issue and currently spinning my wheels,....but, HPTuners Support Bill is trying to help.

[Jason B]

The shift solenoids are mislabeled. I wonder how difficult it is to relabel them, I'm guessing it's on the bottom of the list and been there a while.
It's just stupid when you can scan the 1-2 and 2-3 solenoids, yet to manually control them you use buttons labeled 1-2 and 3-4.

I understand it so it doesn't bother me that much, but it makes me wonder what else is wrong in hptuners that I wouldn't catch.
Like this one strange thing I noticed back in 2008. If you log the delivered torque and have a mechanical transmission pressure gauge connected it's awfully strange how, before each shift, the trans pressure goes up along with delivered engine torque, it shifts and goes back to normal. Same as delivered engine torque.

I see no reason why, under steady throttle, the delivered engine torque would go up before, during and come back to normal for a shift. And do it right inline with transmission pressure.

[Hutchinson]

It's just stupid when you can scan the 1-2 and 2-3 solenoids, yet to manually control them you use buttons labeled 1-2 and 3-4.

Yes Sir,....mine is opposite though,....I can only scan a 1-2/3-4,....yet manually control the 1-2/2-3,....weird one is right and the other isn't. Bill at HPTuners Support is forwarding this to their Engineers for fix + review why my 1-2/2-3 manual command is backwards (I've proven it). I think it has something to do with me having a 0411 PCM,....we'll see.
My main question to them was if the PID is simply mislabeled, ok cool,...just please confirm that the software path is right,....and I'll use it,....it's just I'm not sure, given the results I've had.

That engine torque thing is a bit strange for sure,....I'm gonna test mine in a day or two.

[Jason B]

Yes Sir,....mine is opposite though,....I can only scan a 1-2/3-4,....yet manually control the 1-2/2-3,....weird one is right and the other isn't..

It's not just yours thats opposite. Mine is too, and I'd bet everyones is. I bet not many people mess with transmission things and just don't know.

[Jason B]

This is a video of my scanner. Your operation I'm betting is the same.
https://youtu.be/1e1mCBnRueM

[Hutchinson]

BILL @ HPTuners Support - look at the video JasonB made above (I'll email you too, under the same ticket number),.....JasonB nailed it perfectly. You'll have to stop the video at each gear change and see the on/off status of the 1-2/3-4 (supposed 2-3) shift solenoids.
Appears everyone's is like this?,...man, I'm glad it ain't just mine,....and here I thought I had big problems in my truck somewhere. Chased my ass for 3 weeks over this issue, thinking either my newly rebuilt 4L60e/truck/0411PCM had something wrong! We must get this fixed, there's a lot of 4L60e transmissions on the road,....and this is a fairly basic operating parameter/diagnostic aid/issue to fix. Difficult to believe this hasn't cropped up before/been fixed already.

Damn fine work JasonB,..,I never thought about making a video,...,that's *uckin' genius that is. Dammit man, that's good work,....you made my day bro/took a load off my shoulders. I owe you a case of beer man!!!

Your shift solenoid 1-2/3-4 (supposed 2-3) on/off cycles exactly like mine in 1,2,3, and 4th gears,.....1st and 3rd are good,...2nd and 4th Solenoid on/off are ass backwards. This cost me a lot of work, kicking big rocks around my yard, and spewing words a sailor would frown upon. Drained/dropped my trans oil pan twice,.......because I figured HPTuners couldn't be wrong on something this basic, especially since its been out there for years (both the software and 4L60e's). I'm relieved,..and yet, a bit aggravated over this.

And, in the first portion of your video, when your using Controls and Special Functions to manually cycle the 1-2/2-3 solenoids on/off,....i can verify (twice) that if you drop your oil pan, those will be backwards as well,......which is also on the same ticket I currently have in with BILL @ Support. When you click 1-2 on/off, it'll actually cycle the 2-3 solenoid on the valvebody,....and visa-versa. Yet, they show up on the scanner as being right??? (except the 3-4 is supposed to be 2-3),....that threw me off too,..thinking HPTuners software "simply had to be right".

BILL at Support will get this ironed out quickly, for sure. I've seen him work his magic a few times on here.

JasonB,.....you da man!!!

[Hutchinson]

JasonB, the truly wild part about this is - when you physically swap the 1-2 and 2-3 shift solenoid electrical connectors around inside transmission (at the valve body),...then put it all back together and go for a drive/scan,....the scanner's on/off status for each solenoid stays exactly the same as it was before you swapped them around. That's slapass wild there now.

If you swap the two solenoid's electrical connectors around, you should see the exact opposite on/off status for each Shift Solenoid 1-2/3-4 in both 2nd and 4th gear. But,...it doesn't change,....the scan's on/off status stays the same wether both shift solenoids are wired correctly or backwards,..... man, that truly threw me for a loop when I saw that,....thus, knew, something had to be wrong in the HPTuners software.

Here's a pic of my handwritten scan/test results,...
First Chart is correct Solenoid operation per gear,...from the GM Service manual
Second chart is what my original scan/results were for each gear
Third chart is my scan results after I'd swapped each 1-2/2-3 electrical connector around inside transmission at Valve body

IMG_0342.jpg

Yet, the on/off status for each 1-2/3-4 (supposed 2-3) Solenoid didn't change in the scan results? This shows, not only is the Scanner wrong, but the Controls and Special Functions is wrong as well. One can't be wrong and the other right,...their both wrong. HPTuners must revisit this entire software chain to make right.

Weird both, this software and 4L*0e's have been out so long,....and the vast majority of GM based people have them,....yet, this basic operating discrepancy hasn't been identified/fixed before now.

A happy existing customer brings more business to the door, than trying to market new customers with software advances. I know that's debatable,...and yes, you must keep up with everything new coming out,....but, not at the expense of your existing customers,....as 99% of us don't have brand new/last year model vehicles.

We'll see how this goes with HPTuners Support/their response time. I haven't heard anything new for the past two days,...but, this should be an easy/quick fix for them.

[Jason B]

Swapping the wiring from one solenoid to the other isn't going to make the scanner readout different. All it knows is that it sent a signal to the end of that plug.
I'm going to guess you didn't drive it with the wiring switched.

Think of two lamps in your house, a red lamp and a blue lamp. Now swap the plugs on those. Now turn the blue lamp on. You (the pcm) knows the light bulb (solenoid) got power because it came on. It doesn't matter where the power came from all you care is that the light came on. The pcm cares just about as much.

[Hutchinson]

Aaaaahhhhaaaaa,....Ok, put me in the corner with a dunce hat on,......your right! What the hell was I thinking,....or, was I thinking at all? Nope,....man, that was a dumb dumb moment for me,....I'm sure they'll be more of those moments in the future.

Yes, I did drive the truck with the wires/connectors switched around,....because (before I knew HPTuners software was wrong) the Controls and Special Functions showed them to be backwards (when I dropped the trans oil pan/put my hand on each Solenoid and commanded the 1-2/2-3 on/off). When I clicked on 1-2 solenoid, it cycled the 2-3 on/off,...and visa-versa. Thus, I swapped them thinking something must be wrong in my new 0411 PCM/wiring/or something (at the time, I wouldn't have figured HPTuners was wrong).

I only drove it a short distance down the street and came right back because it was bucking and revving a lot. That's the moment I knew something wasn't right in HPTuners software.

Man, I feel dumb for not thinking bout the Scanner not changing,.......

[Bill@HPTuners]

Its currently in our gm engineers work in queue.

[CP_CUSTOMS]

hey all did you guy figure the situation out cause I been pulling my hair out for weeks trying to figure out why my shift in 2-3were non existent even tho scanner showed it shifting... then to day I thought after seeing this I better check the solenoid operation and found that the pattens for a couple gear were off scanner show

1st gear shows 1-2ss/ 3-2ss/ 2-3ss
on/ off/ on


1-2ss/ 3-2ss/ 2-3ss
2nd gear shows on/ off / off


1-2ss/ 3-2ss/ 2-3ss
3rd gear shows off/ off/ off


1-2ss/ 3-2ss/ 2-3ss
4th gear shows off/ off/ on

SO 2ND GEAR SEQUINCE AND 4TH GEAR ARE BACKWARDS right

[Hutchinson]

Yes sir, HPTuners scanner is backwards for 2nd and 4th. See my pic above and you'll see how they read backwards on the scanner. Hope this helps bud.

HPTuners has fixed this issue, but, won't be released till the next software update.