evilseven

Ok, so I have been reading stickies, and old posts and I am coming up with nada. we have a 6.0/4l80 swap in a Cherokee we are trying to get up and running. The engine is a junkyard sourced LQ9 out of a 2005 Cadillac, the trans is a 2001 (I believe) out of a 2500 silverado, and we have a new painless wiring harness, on which we did the pin conversion at the transmission (like painless instructed.) The pcm was a blank 0411 unit which was purchased online. I have the tune out of my 2001 silverado 1500HD which is a LQ4 6.0/4l80 combo. So, we did a write entire on the pcm with my tune. The jeep runs great, but we have no gears. Well, it thinks its in 2nd, no matter where the selector is. Its like the pcm doesn't know the trans is in gear. I realize now after about 4hrs of reading that the way we went about it probably wasn't the correct way, but thats how you learn I guess. My question is, do we have a hard wiring problem? Or, is it pcm related? I need to get this figured out, because this is the whole reason we opted to bite the bullet and buy the hp tuners software. At this point I dont know if we need a relay wired in or if I Have something screwed in the segment section. If I pull up the tune for the jeep, it reads my sliverados vin, OS, and the 4l80e trans. Any help would be much appreciated.

Thanks, from a newbie

clinebarger

Any codes set?

evilseven

P0443 EVAP purge control circuit fault
P0463 fuel level sensor curcuit signal high/open
P0650 MIL control circuit problem
P0748 pressure control solinoid electrical
P0753 1-2 shift solinoid "A" circuit fault
P0758 2-3 shift solinoid "B" circuit fault
P1860 torque converter clutch solinoid

clinebarger

Check for Ignition power on pin E at the trans plug.

evilseven

key on correct?

clinebarger

Correct.

evilseven

Yes we have power there.

evilseven

not sure if it matters at this point but the output speed sensor is not hooked up seing as we got the tcase from the junk yard and we haven't acquired the correct sensor. And an update, when rolling underneath to check the E pin for power we found the trans hareness unplugged (our bad it was getting late and we were trying different things) So now we know, we do have power on the E pin, and its setting no trans codes with the plug connected. Still only "in" 2nd gear

clinebarger

What gear is the PCM commanding? What is the commanded state of the 1-2 & 2-3 shift solenoids when D4 is selected?

4L80E....
Command gear, 1st.
Shift Solenoid state, 1-2 SS-On, 2-3 SS-Off.

4L60E....
Commanded gear, 1st
Shift Solenoid state, 1-2 SS-On, 2-3 SS-On.

If you still had a 4L60E (Segment)....It should set 3-2 Solenoid & TCC Enable Solenoid codes that the 4L80E doesn't have.

evilseven

I will have to check this next time im at his house, hopefully wednesday. I didnt do a segment swap, I took my whole tune from my 2001 silverado 6.0/4l80e and did a "write entire" on his 0411 pcm. If i get into his pcm now, it looks exactly like my silverado pcm. Coincidentally my silverado also has a 0411 pcm. Thank you for your help so far, I will post after I check what you have told me to.

evilseven

Ok, so no matter how we command the pcm to shift the solenoids stay closed, and the pcm thinks its in 2nd gear. Also looking into possible front pump failure. As i said this is a junkyard trans so it all up in the air at this point.

clinebarger

What are the Fluid Pressure Switches doing? Are they changing state when shifting trough the gears?

Pump Failure......You will know when that happens!

evilseven

I will have him check those, but it acts like it has no pressure. we were kind of thinking that to, but wouldnt a pump failure make some kind of noise? Or not necessarily?

clinebarger

No pressure? It has Reverse & Takes off in 2nd....Correct? It takes pressure to do those two things. There is a reason the PCM is commanding 2nd gear while in D4 range with the OSS/VSS reading zero......Most possibilities of this happening involve Trouble Codes because electrical/solenoid issues.

The Pressure Switches tell the PCM what range the Manual Valve is in, Here are the logic combinations.....

evilseven

Cool, that helps me out. And to answer your question. We have never had revers, And even "in" 2nd gear it has Zero power. Still no codes, I realize that there may be a mechanical issue, but i need to nail down what I should be seeing in the trans. No matter what we command, and no matter where we put the shifter, the scanner shows 2nd gear. The tires will rotate forward if the rear is in the air, but will not move the jeep if on the ground. Even if the trans was junk, We should have codes, and be able to select a gear, correct?

evilseven

He is going to check pressures tomorrow, is it possible we need to re pin the harnesses at the pcm for the 80?

clinebarger

You said stuck in 2nd gear, Which I assumed that meant it took off in 2nd gear.

Wreaking yard unit.....Is the Filter in place? Wreaking yards usually drain the fluid & pull the filter.

evilseven

Ok, I apologize for the misunderstanding. We have never had the jeep move under its own power. Even when we had the 5.3/4l60 tune in it. So, the next step is going to be,
1. drop the pan, check filter, and inspect for general damage.
2. make sure he pan isn't smashed into the filter causing a fluid starved situation.
The trans was purchased from a recycler, that basically just pulls stuff out. The converter is the one that was original to the trans, and all we did was dump the converter and assemble everything. We were planning on a fluid change and filter after we at least saw it move. The trans did sit in my garage for a year, and then has been in the jeep for a year, and im not sure how long the yard had it in their shop. Is it possible for the solinoids to be stuck? Is there anything else we should check while the pans off?

clinebarger

Solenoids will NOT cause a lack of Reverse & Forward movement.

Cool28

iTrader: (2)

is the harness for a 4l80e or just a normal harness. I know with my harness for a 4l80e I had to repin the plug. I believe that's why its staying in 2nd. Have to look around but there should be a page that shows what needs to be changed