TCC LOCKUP 4L60E/LQ4 SWAP WIRING.

[K5Luisg]

so im starting on the wiring for my truck with a lq4/4l60e and was wondering if I could use the tcc wire (prple) for the 700r4 on the 4 prong plug instead of having to setup and wire some relays.
seems like it should already be setup to disconnect power when brakes applied ? any insight on this from fellow swappers?

 

[bigblock72]

You'll need to keep the TCC wired the way that it was in the donor truck or it will set codes. You need to get a wiring diagram of the 6.0/4l60e and a diagram of the 700r4 and you'll see the difference. You can still use your current brake switch and wire it to the brake switch input of the PCM.

Are you modifying the harness yourself or did you get a pre-done harness? Who is programming the PCM?

 

[K5Luisg]

Harness is stock Yukonxl harness with stock fusebox. Calspeed is doing the computer reflash for me.
How does the tcc lockup work in a 700r4?
4l60e should have 12v except when the brake pedal is pressed.

 

[bigblock72]

On a 4l60/80e there is only one power wire going to the trans that powers all of the shift solenoids and the TCC solenoid, if you interrupt that power wire it will turn off any shift solenoids that are on, default to second gear and set multiple transmission codes.
There is however a brake switch input that will turn off the TCC and the cruise control at C1 pin 33 and should be a purple wire. This wire is not necessary unless you plan on running cruise.

 

[K5Luisg]

I do plan to use cruise control in my rig. the tcc wire from the 700r4 is it normally closed from the brake switch and opened with the brakes applied?
also pin 33 should be hooked up regardless if your using cruise. its to unlock the torque converter when your coming to a stop.

 

[bigblock72]

I do plan to use cruise control in my rig. the tcc wire from the 700r4 is it normally closed from the brake switch and opened with the brakes applied?
also pin 33 should be hooked up regardless if your using cruise. its to unlock the torque converter when your coming to a stop.

Yes the TCC portion of the brake switch is normally closed and will work fine for pin 33

My brake switch input has never been connected and the TCC works just fine, the TCC disengages below about 35 mph or so, the switch is just redundant.

 

[K85 Octane]

let me look, all my wires are still marked and hanging out, haven't connected anything yet

 

[K85 Octane]

pale blue for CC

 

[K85 Octane]

Indeed solid dark purple

 

[MAX89K5]

so im starting on the wiring for my truck with a lq4/4l60e and was wondering if I could use the tcc wire (prple) for the 700r4 on the 4 prong plug instead of having to setup and wire some relays.
seems like it should already be setup to disconnect power when brakes applied ? any insight on this from fellow swappers?

Yes, you can. The existing purple wire for TCC provides the correct output for the LS transmission. I have done it and it does work.

 

[K5Luisg]

that was the answer I needed. ty max hoping to fire it up tomarrow excited like a kid on Christmas !!!