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now that its out of the car, how do i hook up a toggle switch to engage lock up. which terminal on the existing plug and does it need any 12 volts or relayed high amp 12 volts?
Can't tell which terminal, sorry don't have a manual handy. It is not very high amperage, less than 10 at least. The way most aftermarket kits do it is as follows: 1 terminal is ground (in a computer car this is the one the ECM grounds). 1 terminal is 4th gear, it provides a ground (to the ECM) that tells you that you are in 4th gear. Most aftermarket kits tie these together so that you provide a ground only in 4th gear. Another terminal is for 12v ignition switched power. Kits vary here. Some have vacuum switches so you only get power when you have sufficient vacuum (cruising), some also/or have power switched by the brake pedal.
I would use some of these things and not just a toggle. You will burn the converter lockup up if you aren't careful.
Well i have mine like this newer style brake light switch ,1 wire comes out of that that is 12 volts going to purple wire at plug on tranny which i think is A i have D grounded to the case.WHen the brakes are applied it unlocks stopping the 12 volts going to the plug.You can just put a toggle switch between the 12 volts and turn it on and off.
now that its out of the car, how do i hook up a toggle switch to engage lock up. which terminal on the existing plug and does it need any 12 volts or relayed high amp 12 volts?
I ran a wire from one of the unused slots in the fuse panel with a 25 amp fuse to a 50 amp lighted toggle switch on the dash and then of course down to the 700R4 tranny Sel. It worked for 18 or so years. I think that the switch went bad one time. Your not even flowing all that much amps so the 50 amp is overkill to make it last longer before carboning up.
I've read this link before. It really doesn't seem possible. If there is no cooling without the TCC locked, the trans would burn up the first time anything was towed up a long hill.
It has been said before in other places:
"Also note that the GM 700R4 (4L60) transmission does not route fluid to the cooler unless the TCC is locked."
I thought it does NOT route fluid to the cooler from the converter when it WAS locked, but DID route fluid to the cooler from the pan always.
You are pulling hard, trans heats up, converter locks with hot fluid in it, fluid in pan cools, hit next hill, converter unlocks releasing hot fluid to cooler, but fluid gets hotter, visious cycle.
Just after having a 700r4 put in my 69 I blew a cooler line hose connection. In one block It pumped out 6 quarts of trans fluid, and I am sure the tc was not locked up because the power switch was not on!!
how does it signal to the tranny that its in 4th gear? Does it ground out the b terminal to signal 4th gear operation?
Depends, in GM O/D many times the 4th switch is NC (normally closed) & would need to be changed to NO (normally open) so it would gnd. the lockup in 4th.
As Ganey said, it all depends on how it's wired up inside. On my BTO 200-4r Pin A gives TCC lockup in OD & pin D gives lockup in 3rd gear (apply 12V to the pin, I guess the ground is internal via the case). My Th350C needed 12v on pin A & pin D was ground (via the ECU). None of this helps you apart from the fact that I measured the resistance of a new TCC solenoid for the TH350C. It worked out that it would draw 0.5A at 12v. I've wired 12v directly from another brake switch on the brake pedal to the trans & have had no problems with large sparks, melting wires, or burning smells! ie it appears that you don't need to use a relay in the circuit (assumint the 700 TCC solenoid draws a similar current).