4l80e tcc wiring...again

[jay_rich]

Okay So last summer I was having an issue wih my 4l80e swap.

2005 5.3L
411 Fbody PCM
4l80e segmant swap.
1997 4l80e
HD2 kit
Triple disk converter

What was happening is the pcm would not control lockup. I could manually lock up the converter using the DVT tab. The other issue I had was in 1st gear after around 145 degrees or so the trans would chatter only in 1st gear like the converter is locking up.

So I put this off until the end of the season and had my trans guy go for a ride. He was stumped and was a GM tech trans guy. Asked a few buddies and they came up with saying TCC must be locking in 1st gear. Gotta be wiring or the programming.

Currently I believe I have PIN S on the trans wired to Pin 33 on the blue connector. Wired to my brake pedal. I have verified this is reading correct as well.


I am not at all ends and debating doing route two for tcc wiring. How exactly would I wire the false relay if I decided to just go back to the 4l60e segment. I think my last test would be to pull out Pin S on the trans and drive it to see if I have any noises. I Almost just want to put a damn manual lockup switch in it!


Thanks

Jay

[joecar]

...

Currently I believe I have PIN S on the trans wired to Pin 33 on the blue connector. Wired to my brake pedal. I have verified this is reading correct as well.


I am not at all ends and debating doing route two for tcc wiring. How exactly would I wire the false relay if I decided to just go back to the 4l60e segment. I think my last test would be to pull out Pin S on the trans and drive it to see if I have any noises. I Almost just want to put a damn manual lockup switch in it!

...What was signal Blue pin 33...?

Post your vehicle's wiring diagram (or rather, how your PCM is wired to your trans).

[joecar]

If you can manually lock the TCC from the scantool/DVT, then the problem is most likely in the TCC apply/release tables and/or a touchy/intermittent brake switch (seen by PCM).

Are you sure the PCM is not seeing any misfires...?

Are you sure the PCM is not seeing any "rough road" indicator from the ABS module...?

[jay_rich]

Sorry should have specified this is swapped into a 1987 camaro. No ABS

Basically I took the 4l60e wiring and switched it as per the swap guides. Removed PIN S and PIN U on the trans connector. Installed PIN U into PIN S and added the second VSS.

Im basically trying to find out which pin on the PCM PIN S should go to. Im wondering if I have it mixed up somehow. I wired the car a year ago and have been driving it, just dealing with this no lockup issue. But like I said it will lock up when I force it.

Ill try to trace the wires tonight if I have time

Jay

[joecar]

Jay,

What year/model/vehicle was the donor for the PCM...?

[jay_rich]

The PCM is from a 1999 trans am but I did a 2002 OS swap on it


Jay

[jay_rich]

it appears I have the pin from the trans hooked up to the correct spot. PIN 2 RED connector.

After doing some reading I noticed a few threads where it said if you have the trans diagnostics set to X not reported it could mess up lockup. So I compared it to a stock 2002 4l80e tune and mine is way off. I forgot that my base tune was from my buddies car which was a t56 car. Basically anything transmission related was shut off. I went through and copied the 4l80e setting them to C:NON-EMISSIONS.


Think this could have been causing the converter not to lock but would lock when commanded?


Im still stumped on my grinding noise. To me it sounds like the converter is locking in first gear at anything over 140 degrees F. Trans guy says its tune related. But 4l80e's wont allow 1st gear lockup. Only other thing I read was it could be a solenoid leak which is common? Its a fresh rebuild with an HD2

Jay

[joecar]

I think you should do another segment swap from a known 4L80E file with the same OS id...

post your tune file here.

It depends on which codes were disabled.

If converter is locking in 1st then I would do that ^ (1st line above).

Even if converter is locking in first, there should be no grinding sound.

Solenoid leak... IDK, let me look at a hydraulic schematic...

[jay_rich]

Here is a copy of one of my tunes from last summer. Camaro-1.ctz. This tune was based off a t-56 tune(diagnostics etc)

I also attached a copy of my newest which I changed all of the transmissions DTC Processing enablers to what a stock 4l80e tune has. C:non-emmisions.

Another thing I get a slam when going into reverse. Would altering D1505 help this. I currently have it set to zero. I assume a negative value would put less pressure going into reverse?

Im just trying to rule out all options as my builder thinks its tune related. Some threads online are telling me its a cross leak. I also heard the 4l80e has pressure issues as is and there is a modification places like jakes do.


Thanks

Jay

[jay_rich]

So after a year of figuring this issue out...im starting to get somewhere. Like I said about I had all the MIL's set to NOT REPORTED. Now that they are reported I beleive the trans is going into limp mode.

CODE P0713- Temp sensor
CODE P0748- Pressure control solenoid.

Im thinking the internal harness may have some issues since it was reused in the rebuild.

Jay

[Chevy366]

If it were me I would start over with a good 2002 4L80e tune, full flash and copy all the engine tuning from your tune to it. Believe it or not from experience, a segment swap can miss some aspects of the engine segment when doing a trans segment swap. They do commingle somehow.

[jay_rich]

Also I just noticed this upon starting over with my trans tune. I did my COS setup I think before I swapped the trans segment. Didnt even think to check the trans diagnostics.... I have the maf codes on for the trans still! Maybe this is whats causing that slam going into reverse and the chatter in 1st? Maybe too much pressure? Im also at the point of doing a stand alone TCM. My friend has one I may borrow if I cant figure this out.

19393

[joecar]

Yes, you want to inhibit the MAF DTC's in the trans fault and max pressure DTC tables.


If you did the COS upgrade (full flash of empty COS file followed by cal flash from OEM file), then you would have to do the segment swap for both the Transmission segment and the Tansmission Diagnostics segment after the COS upgrade.

[jay_rich]

Well somewhat good news. The harness fixed the P0713 temp code! But I still have the P0748 code. I shut off the maf trans faults. Maybe there is something im missing? I have heard of getting this code with stall converters as well. I think my best bet is to drop the pan and check the resistance to make sure the solenoid is good.

Jay19394

[joecar]

Also:
D0910,1,2 WOT 1->2 MPH and D0925,6,7 WOT 2->1 MPH are upside down.
Set D0960,1,2 to 100%.
Be careful, TCC might apply in 2nd gear (2nd gear multiplies torque sufficiently to slip the TCC lockup).
Set D1101,2,3 to zero (i.e. non-negative values).

Also:
set B3609 to zero.

[jay_rich]

Strange thats a pretty well completely stock 4l80e tune! I swapped all that. Im going to do a scan to check the EPC and see what its reading. Im also reading this is a common code with aftermarket converters but It literally popped up idling in my garage. Also still slammed reverse with the stock settings.

Ill try these settings later. I did change the 2nd gear lockup as well.

Thanks

[jay_rich]

Well did some more messing around. still getting the P0748. Im thinking the solenoid is dead. Even using the DVT tab and forcing current, it doesnt change. Unless something in the wiring is shorting. I made sure the pins are correct on the PCM

Jay

[joecar]

Yes, stock truck tunes are not that good from GM.

Unplug the PCM connector, and ohm the EPC from there.

[jay_rich]

Thats the plan today, should have did that the other day. I put my PCM in such a hard place to work on. Ill check there and see what i come up with then call my transmission builder.

[jay_rich]

Ugh....all that bs for a wire frayed 6 inches from the PCM. Of course I dropped the pan first...19412

[jay_rich]

Well its amazing how smooth it shifts now that its fixed! No more codes, slamming...Chatter not sure yet I didnt drive it long enough.


Jay

[jay_rich]

Seems like the chatter is gone and it locks up on the highway! All that pain for one wire! Drives so much nicer now.

Jay

[joecar]

Good job :cheers:


What caused the wiring to get damaged...?

[jay_rich]

I repinned a stock truck harness. It was frayed before I even taped it up! Didnt notice it when I was wiring it. Note to self check EVERY wire. lol

Jay