tcc brake switch ??
 

I am reworking a blue green harness and on the blue side pin number 33 is purple tcc brake switch wire can I just splice it in the hot wire to brake switch ? or splice it in the brake light hot side brake lights on ?

Re: tcc brake switch ??
 

No, you need to hook that to an ignition 12v, but that gets cut off when the brakes are applied. Do you have a 4 prong brake switch? You will need one if you don't. Here's a pic I stole from this site somewhere, but should help.

There will be a light blue wire on the TAC plug, pin 6 that goes to the cold side of the brake light switch, and you can hook that one up to your original brake light plug as it will need to see 12v with the brakes applied.

Re: tcc brake switch ??
 

ok my truck does not have that just 2 I got one on the way. I have been driving the truck for a few years without it never no problems other than the overdrive been having to back off the throttle for it to go in overdrive maybe this will solve that it looks just like that.

Re: tcc brake switch ??
 

I bought this tcc switch and the destructions don't say anything about the light blue wire going to the tac module http://www.psiconversion.com/instruc...STRUCTIONS.pdf

Re: tcc brake switch ??
 

That's because the instructions aren't for the whole engine harness. The GM manual shows it, I posted a pic of it in the cruise control thread, post #18. Light blue wire, pin #6 on the TAC plug. Needs power when the brakes are applied. http://67-72chevytrucks.com/vboard/s...d.php?t=511477

Re: tcc brake switch ??
 

I got the tcc switch installed can you tell me what it does ? I cant tell any difference with it hooked up.

Re: tcc brake switch ??
 

arnt you using a nv4500? or am I getting you mixed up with someone else?
the tcc switch disengauges the torque converter clutch (tcc) when you slow down...

Re: tcc brake switch ??
 

here it is explained.....https://www.freeasestudyguides.com/a...er-clutch.html

Re: tcc brake switch ??
 

no I am running a lq4 6.0 with a 4l80e and np205.. the engine and transmission came out of a 2006 2500hd 2wd and its in a 77 k3500 crewcab when i did the swap I never hooked up the tcc wire I thought it was just for the cruise.i have always had to let off the gas pedal just a little for the transmission to go into overdrive and it seems to just glide into overdrive not just shift rite into it. I have been driving it for about 4 years without the tcc switch hooked up I drove it for a short distance today and it seemed then be the same but I will try it out and drive it a little more and see how it does .thanks for the info on the tcc I never knew there was a clutch in the torque converter.

Re: tcc brake switch ??
 

Really thank you, it is good information for me TCC . I have question that wire coming from TCC to pcm where exactly going to ?


Thx.