rpm-inc

iTrader: (2)

TCC Brake signal. Do these pins need 12v when brake is applied or not applied???? Getting confliciting info on the net.

Car it is going in has a normally closed brake switch. 12v when brakes not applied.

Close to finishing up the wiring. Don't want to damage anything wired wrong. Thanks!

trozfan

I don't have the brake switch installed on my swap yet but here is the wiring for the factory plug. Hope this helps

trozfan

Just found this too. It looks like it gets 12v along with the brake lights when the pedal is pressed

1989GTA

I don't quite remember how I did mine except that I used a brake switch with a double switch. One for the existing brake light circuit and one for the transmission circuit. I believe I wired it like shown in the above schematic but used a resistor to simulate the brake lights(J231, J123).

So the voltage at X1-6 of the 6L80 would be "grounded" through resistor and when the brake is applied the voltage at X1-6 would rise. You will notice an internal resistor at X1-6. I believe and not sure but the part the goes to X1-9 on the ECM is the normally open side of the switch. I don't know if I have helped or hurt.

rpm-inc

iTrader: (2)

OK, thanks for the help. Here is the diagram for the external t42 tcm I am using.


Can I just tie 6311 into circuit yel 820 from this diagram then?

1989GTA

The upper diagram shows the blue white wire (6311 or 8311) going to both the TCM and ECM in the lower right corner. If you did use the bottom diagram it appears that you would have to take the signal off at S238? and run it to both the TCM and ECM. Worst thing that could happen is that it does not work. I don't see you burning anything up.