700R4 Lockup Control w/ TBI

[1v6pony]

If your EFI harness was wired right the original transmission wiring you had should have locked up the converter all the time unless you pressed the brakes.

If you've got it wired per the second diagram then you should be laughing. Get that governor adjusted right.

As for testing, when driving a steady speed it should be locked and a light press of the brake pedal (enough to turn-on the brake lights) should show a couple of 100rpm increase.

Just as an FYI, last TCC clutch only setup I ran 5 chip adjustments through it before it worked to my satisfaction. The last 4L60e was about 20 tune adjustments to get the trans decent but it could still use a little more fine tuning.

So her is something interesting on the ATSG. I wired like the diagram in the photo I sent, It shows the neg of the Solenoid going to the 4th Cl switch,,, BUT on the diagram right next to it more like an actual drawing, It says to put the Neg Solenoid wire on the 3rd Cl switch... What is the right way to do it???

[lionelhutz]

I have no idea what CL stands for but the last thing you want is a switch that grounds the negative of the solenoid in 3rd gear or 4th gear. If that happens, the switch will bypass the ECM and the ECM won't be controlling the TCC.

[1v6pony]

Ok, Are you saying that the diagram on the photo is wrong,.
From what I have been told ,the D terminal from the ecm is not a constant ground.. and the 4th switch is an open switch so when the ecm sends the ground then it would control the TCC.... Right???? (see earlier photo I sent)

[lionelhutz]

As I have posted before, I have no idea why that switch is there or what it exact function is.

I can tell you that the ECM will ground the negative side of the solenoid to command the TCC to lock.

I can also tell you that any switch inside the transmission that grounds the negative side of the solenoid will over-ride the ECM. N/O means the switch is normally open but it will close under some condition.

Personally, I'd go from terminal A to the 4-3 downshift switch to the solenoid to terminal D. I'd run another wire from terminal B to the 4th gear switch to ground. Then put it together and see what happens. You will need logging/scanning equipment to be able to tell if the Howell programming is commanding the TCC to lock or not.

Except for adding the 4-3 downshift switch the above is what I posted you should try 3 pages ago.

[spankrjs]

No, you don't have to use the ECM. My opinion is the ECM handles lock/unlock based on speed and throttle position so once you set it right it works rather well. Why not take advantage of the better control logic when the ECM is in the vehicle already?

As for a diagram. Put switched 12V to a brake pedal switch. Run from the other terminal of the brake pedal switch to pin A of the TCC connector. Pin D of the connector goes to the ECM. Internally connect the solenoid between pins A and D.

I know this is an old thread, but I have a question that involves ECM TCC Lock Up.

I am using a 1991 Caprice Classic 5.7/700R4 in my 1984 Jeep Scrambler. I am using the ECM to control TCC lock up function. According to the scan tool/tach/seat of pants, I can verify that I get TCC lock up in 2,3, and 4th gears. But, the scan tool is saying "Top Gear Not Indicated"??? I know I am going into 4th, and I know the TCC is locking, so what gives?? I don't have any error codes, and I am using a VSS, axle gears are 4.10 with 33" tires, transfer case speedo gear is correct for tires and gears.

I seem to remember that the scan tool would read "Top Gear Indicated" when the transmission was in 4th, but I am not getting that signal anymore. But, TCC functions like normal as far as I can tell???

Could the 4th gear pressure switch in the transmission broke??

I am getting TCC lock up in 4th, just kind of confused about the "Top Gear Not indicated" feed back?