I've done all kinds of searches, and found TONS of info on switches for those of you that have removed the EFI and gone with a carb.

What I want to do is simply be able to turn off the computer control for around town. I get into 4th gear here and there, and I'm gonna have 3.73's soon. With the new mods, tranny, TC etc. I don't like it locking when I'm in fourth gear around town. However, when I drive on the highway, I want to flip the switch and let the computer handle the TC lock-up.

Currently highway driving is no problem, but around town it locks too early.

 

I just re-read the tech article, and that's NOT what I want to do. In case it wasn't clear:

The switch I want will switch from normal computer to controlled TC lockup, and no-lock-up at all in any gear. Kinda like the reverse of the tech article.

 

It's very simple, I did a manual lockup switch yesterday, works just fine.

I bought a self illuminating rock switch at pep boys for like 4.99$.

Take power directly off the battery and run it to the switch. Ground the switch.

On the driver side of the transmission you take the connector and use only the ground and power. You run a line from the power of the connector to the other side of the switch and ground the connector to the frame. My buddy made a very nice wiring diagram in AUTOCAD and has digital pictures. I'll post them tomorrow if you'd like.

 

YES, a diagram would be GREAT!!!

You're talking about the 4 prong connector, right? ...and you're saying to only use 2 of the 4? (power and ground).

In a sense turning the TCC on and off? ...if I'm understanding you correctly.

 

Yes, the connector has 4 prongs, but only 2 are used for the manual switch. Power and ground. Basically, your running 12v directly off the battery (with a 20A inline fuse of course) and sending it to the connector. You wire a switch in between to toggle the power on and off. Grounding both the switch and the connector. I'll get the diagram for you tomorrow as well as pictures of the installation.

It's very simple to do, requires about 10$-25$ depending on what you have and how nice a job you do (I did all soldered connections with shrink tube.)

My friend has a lift in his garage, so I had the luck of being able to just bring the car up and down whenever I wanted. So running the wire under the car and in the engine bay was done very cleanly.

I do not reccomend buying an aftermarket lockup kit as they are overly complicated and in my buddies case they locked the converter up as soon as the trans goes into 4th which is annoying for driving around. B&M sells an adjustable lockup kit that you can adjust to lock up at a certain speed (via vacuum adjustment) but it's about 150$.

The manual lockup switch is easy to do, you don't have to drop the trans pan, and costs 20$ to do compared to a kit (70$ for the cheapo kit that locks up as soon as you go into 4th)

 

Yep, it makes sense. I agree with your reasons for not using the other kits too.

....I'd like to see that diagram!

 

If that's the case, the easiest thing to do is to interrupt power going to the TCC solenoid through the brake switch....remember, the TC will unlock when the brake pedal is pressed.

Simply put a toggle switch inline on the pink/blk wire going to the brake switch. When you flip the switch you are removing power to the brake switch....basically the TCC solenoid "thinks" you're stepping on the brakes (even though you're not) and will not energize.

Flipping the switch back will restore power going to the brake switch and the ECM will lock the TC like normal.

 

Is the pink/black wire one of the four going to the 4 pin connector in the trans?

...I guess it would have to be, no?

 

Well, yes....power is sent to the brake switch through the pink/black wire. Then from the brake switch should be a purple wire that goes to the 4 pin connector on the trans.

By wiring it the way I suggested, you do not need to get under your car to mess with the 4 pin connector. Simply find the brake switch under the dash and go from there.

 

Abubaca, my buddy is going to email me the diagram when he can. Hopefully I can have it up tonight if you still need it.

I noticed in your other post you said your trans would lockup in 3rd gear.

Is this normal?

Can I switch my lockup on when I'm in 3rd gear driving around town doing 25MPH? Will it harm anything? Right now I only turn lockup on when I'm doing over 40MPH.

 

Thanks for the diagram. IROCZZ3 seems to have a better way though. Keeps all the wire splicing under the dash.

....as for the third gear lock-up, I guess that's normal. I could never feel the lock-up with my stock set-up, so I never even thought about it. With the new TC, I can sure feel it.

I'm not sure about how your car drives, but for me, I plan to only use the TCC on the highway. Around town I don't cruise at speed for long enough to warrant the lock-up.

 

My mechanic wired me up a TC cancel switch via the brake cancel method mentioned above. If I leave the car in third, the TC will lockup at about 50mph... Jimmy (my mechanic) also told me that the computer will command TCC lockup in third as well as fourth gear.

Like you said, you just don't notice it with the stock converter.

 

Has anyone done this? If so could I get a simple step by step on how to do this because my tranny is locking up in 4th at about 35mph which is about 10mph too soon and is causing my car to shudder a bit.

 

Bump

 

Visit the DIY PROM forum. Search TCC.

 

Took a look at the PROM section....im not very good with messing around with Jumping pins and all that stuff. I just want to do the simple toggle switch from the brake comnector. I just need to know which wires i need to wire the switch to for sure.

 

Bump

 

At the brake pedal will be a switch with a pink/black and a purple wire. That is the TCC switch. Note that these colors are for a '92 L98, but are 99.9% likely to be the same on your '90.

RBob.

 

Thanks RBob....heading out now to do it.

 

Ok obviously I am not doing something right or not using the correct pink/black wire. I vampire clipped 2 different pink/black wires that I found under the dash and then hooked the other end to a rocker switch.....maybe I am just an electrical fool but the switch didn't work. I have a rocker switch that has 2 prongs, one for power the other ground I assume, I try to find the correct wire under the dash coming off the brake connector but there are a mess of wires under there and honestly I see multiple pink/black wires and a few of the purple too. Is the connector I am looking for ONLY have the pink/black and the purple wire coming out of it or are they in a bundle of other wires too? I have some pics....hopefully someone can recognize what I am looking at....also I ran one wire from under the dash just to one of the prongs on the switch, I have no idea what to connect to the ground part of the switch. You can also see what wire I tried to vampire clip in a couple of the pics......I am so lost lol......

 

Bump

 

Bump

 

The pink/black wire is IGN+ switched, there are a bunch of them.

Look at the brake pedal assembly, up further. There should be one or two push type switches mounted on a bracket. The plunger of the switch contacts the rear edge of the pedal arm.

Wire the rocker switch into the cut wire, with one end of each end of the wire on one each of the terminals on the switch.

Basically, splice the cut wire back together using the rocker switch. Don't ground anything.

RBob.

 

Ahh Ok so I was looking at the wrong wires....as you can see the wires under my dash are like spaghetti (not my doing). I think I know what switch on the pedal arm you are talking about..its hard to see becuase there are so many wires around it. So is the cut wire you are talking about already cut? Is it still a pink/black wire? Sorry I have so many questions, I just dont want to splice into or cut the wrong wire and create a whole new problem Thanks again for your time RBob

 

Not already cut, once you find the correct wire you need to cut it. Then wire the switch in to those two wires. So that when the switch is 'off', it is the same as the wires being open (cut).

That will prevent the TCC from locking with the switch in the off position.

Note that you can do this with the pink/black wire or the purple wire.

RBob.