I've got a bit of a Strange issue on my hands.

I did a LSX swap into a 67 A body, everything else is great.. Except the Torque converter will not disengage.

Here is where I have started my Diagnosis

#1
Check my brake switch, Check the relay, trace the 12V signal to pin 33 (12V @ rest, 0v when you press the brake pedal)

That all checks out.

#2
Drop pan, Inspect TCC solenoid, remove solenoid, depress valve going into the pump..

All of that checks out. Trans. is Brand new maybe 15 miles on it and some dyno time.

All of the wiring for the solenoids internally checks out no shorts

#3
Check PCM TCC output pins
Pin#2 - constant 12v, no actuation with the brake pedal.. There was no change in voltage.
Pin#42 - Same as above..


So I assumed I must have set the converter to 100% lock up while on the dyno.. So I open EFI live and pull the data off of the PCM..

Settings are 100% stock for the Trans..


So, my Question is why isn't the PCM telling the Solenoids to disengage ?

And, What should the voltage @ Pin #2 and Pin #42 be when the brake pedal is at rest and when it is pressed?


Thanks for your help

 

As far as I know the tcc circuit is supplied 12 volts all the time and is switched on the ground side.