Whats this for?

[sunnyc123abc]

Well, im trying to figure out why my torque converter lock up isn't working. I think its an electrical problem, so i was checking some stuff with my meter, and then i saw this, which i believe is the brake switch for the tcc. But what is the hose comeing out the back of it for?

 

[maynardogle]

Probably dumps the vac motor on the cruise control.

 

[sunnyc123abc]

That could be it. But there are two switches connected to the brake pedal, and I thought the other switch was for the cruise control, and brake lights

 

[pauly383]

I don't really know about your year of truck . But in my 83 , I have a switch for the pedal so it unlocks when brakes apply . I also have a vacuum switch on the firewall so the tranny knows when I am cruising .

 

[sunnyc123abc]

its an 84. So do you have two switches right next to each other on top of the brake pedal?

 

[Russell]

One switch does your brake lights, and cruise control, the other switch does your TCC, and dumps the vac motor as suggested

 

[p.o.s 78]

Who would carry the switch, i went to autozone and they couldnt even order it

 

[rampage]

Did you check here at LMC?

 

[badmix]

Brake light switch or TCC lockup.

Can order from ROCK AUTO.com or maybe LMC.com

When my TC wouldnt lock up, I went thru some steps to diagnose it. First thing was to hook up a lil LED idiot light to the 12v wire going to the trans, this let me know that the electrical was working. I had first worried it was the solenoid in the trans that went bad.

I ended up replacing the part under the dash that you pointed out, I also replaced the small lil vacuum thingy on the firewall. It has vacuum line in one side and electrical on the otherside. This is what was bad on my truck.

I just went to rockauto.com. here is the part that is on the firewall that went bad on my truck.

ACDELCO # 212331

 

[Keitha]

That is the CC switch and dump. I bought one from a dealer about 1 year ago. $17 if I remember correctly.

On you TCC, adjust the other switch so that the button is depressed when the brake pedal released.