TCC wiring question???
 

so i got my truck moving today, went around the neighborhood in chill mode, but i still need to hook up my TCC wire, i got a 84 k10 with a cruise control (or used to anyways) and need to hook up my TCC wire for the tq converter, does anyone have some pics of where and what color wire up there by the brake pedal? i seen on lt1swap.com but not good with schematics

Re: TCC wiring question???
 

They hook to the brake switch, which is usually located in the bracket that the brake pedal/arm hang from or bolt to. If you follow the shaft up (pause), you should see the hinge where the pedal connects, and just under that point should be the brake switch. If its a 2-post, you need to pull it out and replace it with a 4-post (part # in my build). This lets you use the two front posts for brake/lighting, and the rear two posts for tcc lock.

Mine was purple, green, pink, and I think some other purple. Three of us were working on the wiring at some points, and I'm colorblind...so yea.

Re: TCC wiring question???
 

These two or four post?

Re: TCC wiring question???
 

#2 pic

Re: TCC wiring question???
 

LOL, how am I supposed to tell you what in front of ya? How many wires are coming off of each?

I'm not a square body expert, but when I searched for image/pn of a stop light switch for your truck, it came up as a 4-poster. When I also searched google for the wiring, it listed the below diagram; which says Yellow, purple, blue and light green wires should be going to it. I can't tell you what color wires are going to be on your engine side harness, but you should have a couple that connect to the TAC and say "TCC" or similar.
http://www.truckforum.org/forums/att...-diagram-2.jpg

Keep in mind, I just looked this stuff up, so the information is only as good as the resources I can find. I also don't know why it looks like you have two of those switches in there.


BTW, did my harness ever freaking show up at your house? After I fv*ked up the shipping thing, I never heard from ya. Apparently the snobs at the UsPs expect me to put zip codes on things....elitists!

Re: TCC wiring question???
 

Sorry, I'm probably too much of a newb, but I don't see the brake light schematic on here, am I wrong?budlight eyes kicking in?

Re: TCC wiring question???
 

The brake light switch should have orange and white wires for the brake lights, they will be on the front two terminals. The back two can be used for the TCC, just hook an ignition power to one terminal and the other will be the wire coming from the PCM for the TCC, but off hand, I can't remember which wire it is, or what color, but should be labeled in your harness.

Re: TCC wiring question???
 

I got the wire for the tcc, just didn't know which wire to splice it into under the dash...by dash I mean the brake switch

Re: TCC wiring question???
 

Do I need to splice it into the orange or white wire I guess is what my newb butt is asking....

Re: TCC wiring question???
 

Run a seperate wire from an ignition power source to one terminal of the rear terminals on the brake switch, then the other terminal gets the wire from the PCM, purple I think. Dont tap into the brake light wiring unless you're using cruise control, then there's a wire that comes from the TAC module.

Re: TCC wiring question???
 

The correct brake light switch has two sets of terminals instead of the standard one set for brake lights only.

The way the switch works is for the brake lights, (normally open) 12V is supplied to the switch and when you press the brake pedal, 12 v is sent to the lights and the brake lights come on.

For the other set of terminals, (normally closed) 12V is supplied to the switch and when the brake pedal is depressed it removed the 12V from the circuit, in this case the torque converter control, (and unlocks the converter)

Here is the one I use (Delco D850A $9.79 with free shipping with prime)

Amazon.com: ACDelco D850A Switch Assembly:...

Re: TCC wiring question???
 

so i have the right one right? that pic looks like the one i have, seems pretty simple, I'm going to tackle this after i get back from my physical...i would do it right now but i just got out of the shower and seems like no matter what i do with my truck i always get covered in oil and grease!!!

Re: TCC wiring question???
 

I'm reviving this one.

So....I finished my swap looong ago. I never messed with a "TCC/Brake switch hookup" when I was near completion. What's the purpose of this? Doing it makes the vehicle do what? If you don't, what does the vehicle do or not do?

Just asking because I'm having issues with my trans(4L60e). When taking off from a stop light aggressively, after it has pretty much sped up to shift from 1st gear to 2nd gear I have to let go of the gas for it to shift, then while in 2nd gear and attempting to rev and speed up, it feels like it slips. 3rd and 4th work like a charm. I have not noticed this happen too often when I feather the gas pedal.

Just wondering if not having done a TCC/Brake switch hookup has contributed to this.
BTW I should mention this whole issue started after it downshifted several times after passing a couple of cars at pretty fast speeds.

Re: TCC wiring question???
 

Not hooking it up will cause issues related to lockup. What your describing sounds a little more like a line pressure issue.

Re: TCC wiring question???
 

Hey Brew

Thanks for responding to the thread. How you alleviate or troubleshoot this? I can this of checking for leaks right?

Re: TCC wiring question???
 

Do you have HP Tuners, or a scanner that can read trans position?

If not thats ok, but if so it makes life easier.

First things to check when you have any GM auto tranny problem; Check that the fluid is good and at the correct level. Then undo the wiring connectors on the side of the trans and hit them with electronics safe contact cleaner, and re attach them. I like to also undo the battery for a few minutes, so the trans starts "fresh" and the ecm relearns. Also, make sure your dipstick locks all the way down (it actually makes a huge difference).

Sometimes this clears up little annoying issues, however what your describing may be a little more mechanical than that...but you've gotta do the easy stuff first.

If ClineBarger pops his head in here, he's the go-to auto trans guy. I do know sometimes the little check-ball in the valve body gets stuck and causes line pressure issues..

Re: TCC wiring question???
 

Cool man. Good looking out. I'll start with the easy stuff first. I have no HPT or anything of that sort. I'll have it scanned at the parts store.

The oil has less than 1500 miles on it. It does smell a bit "old" considering I just changed it when I completed my swap (1500 miles ago).

Thanks again.

Re: TCC wiring question???
 

Hey guys so I recently swapped a vortec 5.3 with a 4L60E On my 70 c10, everything was working fine until yesterday. I was driving down the street at about 30 mph. I got to a red light and when I went to go the rpm’s got high and first to second gear started slipping 2-3 gear was fine. Fluids are good and full, it didn’t smell burnt or anything. I hooked up the TCC brake switch. Anyone have any ideas what the issue could be? The tranny is used out of an 02 Avalance 2wd. I never changed the filter when I installed it so could that have anything yo do with it? Any advice is greatly appreciated since this is my first time I do a swap

Re: TCC wiring question???
 

I owe someone a big thank You. I was told by my ex wiring/PCM re wirer that the TCC wire goes direct to Positive all the time. Wow I would have had a problem. My wire is PURPLE Thanks again As I say my programmer is my ex.