[gsoleski]

I have an 84 700r4 and I removed the ecm so I lost the lock up. I tried to wire up a toggle switch for it but accidently switched pin A and B. So pin A was grounded and is should have 12V going to it. B had 12V through it and its supposed to be grounded. C has been grounded the whole time. Now that I switched A and B around to the way it should be it still doesn't want to lock up. Did I fry something in the trans when I had the A and B switched around?

 

[bigdog7373]

I have an 84 700r4 and I removed the ecm so I lost the lock up. I tried to wire up a toggle switch for it but accidently switched pin A and B. So pin A was grounded and is should have 12V going to it. B had 12V through it and its supposed to be grounded. C has been grounded the whole time. Now that I switched A and B around to the way it should be it still doesn't want to lock up. Did I fry something in the trans when I had the A and B switched around?

First, check all the wires and connections again before you do anything

 

[gsoleski]

I tried that with no luck. I'm starting to think that the solenoid is fried or i'm just not wiring it right. Was thinking to just connect A to 12 volts. Then connect D to ground and put a toggle on each wire. To lock it flip the ground then flip the power. Reverse to unlock. My latest discovered problem is it doesn't shift into 4th. I just started to take the car on short highway drives while i'm testing and noticed it. Gunna try adjusting TV cable tomorrow and securing my shifter cable to the trans better. (clip fell off months ago, its help on by zip ties)

 

[SSedan64]

Could have possibly fried the TCC Solenoid or the 4th Pr. switch. But since it never shifted to 4th they should be fine. The 4th Pr. switch circuit didn't make contact, if it had it would've smoked the 12V+ wire.
You can try running it on Jack stands & shifting back & forth 3rd to 4th to see if it'll make the 3-4 shift. If it will try the TCC Lockup again.

 

[gsoleski]

okay a little update. Re adjusted TV cable and topped it off with a little fluid and 4th gear works. I will be getting a new solenoid today at the local shop. Here's where I need help. I just want to know exactly here to put the wires. No brake switch, no vacuum switch, just the wires and a toggle. I will get just the regular two prong on/off toggle. Does ground (D) to the chassis? Then the toggle goes onto the A wire? Like this

 

[SSedan64]

That may work fine. It depends on which type 4th gear Pr. switch is on the Valvebody, 1-Pin or 2-Pin and 1-wire or 2-wire TCC Solenoid.
You may not need the -Ground wire, only 12V+ to Pin-A.
This will help you understand what I'm talking about:
http://www.crankshaftcoalition.com/wiki/Torque_converter_lock_up_control_700R4

With the Toggle switch you can wire it to Lockup in 2nd, 3rd & 4th gear or 4th only. With a permanent -Ground connected to the Solenoid flipping the Toggle switch would lockup when ever you wanted 2nd, 3rd &/or 4th.

 

[gsoleski]

The solenoid is 2 wire and I think the pressure switch was also 2 pin. I tried my set up in the picture with no luck. Should I ground B on the chassis if that is for the 4th gear switch?

 

[SSedan64]

The solenoid is 2 wire and I think the pressure switch was also 2 pin. I tried my set up in the picture with no luck. Should I ground B on the chassis if that is for the 4th gear switch?

Pin-A = +12V to the L/U solenoid.
Pin-B = 4th gear switch feeds the computer Ground when the Trans is in 4th gear.
Pin-C = 3rd Pr. Switch or (Not used)
Pin-D = The computer feeds -Ground to activate the L/U.

http://www.hughesperformance.com/pdfs/HP700-R4.pdf

It should be Pin-D for the TCC -Ground, Pin-B sends a -Ground signal to ECM indicating 4th gear.
You can give it/Pin-B a try because I can't see how it's wired inside
If that doesn't work something is bad inside, Solenoid or 4th Pr switch.

 

[gsoleski]

I'll try grounding B tomorrow and see what happens, if that doesn't work its gotta be the pressure switch then. Really don't want to take that pan off again.... thanks for your help man. I'll post what happens tomorrow

 

[SSedan64]

If you've got a Volt/Ohm meter try checking to see if you get a -Ground on B or D after the 4th gear shift.

More wiring diagrams >> Lockup TCC Wiring

 

[gsoleski]

well I tried grounding B and nothing happened. I don't have a meter to test the wires either. Should I start looking for a 4th gear pressure switch?

 

[gsoleski]

I'm thinking its the switch because I had accidently wired 12v to it last week.

 

[SSedan64]

https://www.wittrans.com/SchematicParts.aspx?Transmission=700R4&LinkCode=411

700R4 Transmission Parts Solenoids

2004R transmission solenoids, Transmissionparts US.com

Bottom of Pg.
Automatic Overdrive Transmission Swap

There're NO/Normally Open & NC/Normally Closed, 1 & 2 Pin switches, Self Grounding etc...
An Volt Ohm meter is the easiest way to ID them, continuity test.