700r4 valve body wiring question
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Joined: Jul 2006
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From: chiefland fl
700r4 valve body wiring question
hey guys, here is a pic of my valve body and wire harness, looks like i have two pressure switches and a plug, but the wiring harness only has provisions for "one" do i have the right harness? im guessing the wire goes to the switch with 2 connectors on it, i also need to wire in a vacuum switch also so i can lock up the converter because the computer is kaput, maybe i should plug the other switch? safer? or should i connect all three, i have no idea, so any help is appreciated!
my firebird sold the other day so now im in a mad rush to get this thing on the road at least to get to work and back, (not far, lol)
my firebird sold the other day so now im in a mad rush to get this thing on the road at least to get to work and back, (not far, lol)
Last edited by billybonesmusic; Aug 16, 2007 at 09:53 PM. Reason: pic
Instructor
Joined: Jul 2007
Posts: 174
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From: Toronto Ontario
one wire is the TCC (Torque Converter Clutch), the other is the 4th gear switch ( which goes to the ECM telling it the tranny is in 4th gear). The other wire is the speedometer pulse wire ( which goes to the console telling you how fast your going). I can e-mail you a circuit diagram if you so wish. These are the wires coming off the transmission. What you have looks like the TCC servo but i could be wrong.
Last edited by trackman44; Aug 16, 2007 at 10:44 PM.
Le Mans Master
Joined: Aug 2000
Posts: 8,838
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From: Australia
"The other wire is the speedometer pulse wire"
Speedo signal is from VSS in tailshaft housing ;not valve body.
The lockup solenoid has a hot feed grounded back at the ECM.(2 wires)
The 4th gear switch goes to ground at the valve body.
At the external plug (4 holes / 3 wires )
12V is ppl ,
TCC ground to ECM is tan /blk
4th gear switch is lt blu
Speedo signal is from VSS in tailshaft housing ;not valve body.
The lockup solenoid has a hot feed grounded back at the ECM.(2 wires)
The 4th gear switch goes to ground at the valve body.
At the external plug (4 holes / 3 wires )
12V is ppl ,
TCC ground to ECM is tan /blk
4th gear switch is lt blu
Thread Starter
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From: chiefland fl
WAIT A MINUTE! DUHHHHHHHHH, i just answered my own question, since the computer is gone....i have no need for the other pressure switches, i just need the one wire going to the switch with (2) prongs, and hook up a vaccum switch inline with it, and that will control my t/c lock-up function. i can even hook a toggle switch up to it for manual control, ok, im an idiot we did almost the same on my buddies Z28 700r4. sorry, 
Race Director
Joined: Feb 2004
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My favorite way to wire these is for 4th gear only lock up. No computer or vacuum switches needed for this method.
To do 4th gear only, leave the 2 prong pulse swith alone, as it serves as a pipe plug.
Replace the single prong switch that you currently have(normally closed) with the normally open type. I have the gm part number handy and can look it up if you like.
Make sure terminal A has 12 volt ignition power and leave that wire alone. Cut the ground wire on the solenoid and run it directly to the 4the only (normally open) switch in the v/b. That is all there is to it.
There are many aftermarket lock up kits out there, and I do not like any of them. Toggle switch arrangements become a pain in the nuts very quickly. Vacuum arrangements suck as well.
To do 4th gear only, leave the 2 prong pulse swith alone, as it serves as a pipe plug.
Replace the single prong switch that you currently have(normally closed) with the normally open type. I have the gm part number handy and can look it up if you like.
Make sure terminal A has 12 volt ignition power and leave that wire alone. Cut the ground wire on the solenoid and run it directly to the 4the only (normally open) switch in the v/b. That is all there is to it.
There are many aftermarket lock up kits out there, and I do not like any of them. Toggle switch arrangements become a pain in the nuts very quickly. Vacuum arrangements suck as well.
Instructor
Joined: Jul 2007
Posts: 174
Likes: 0
From: Toronto Ontario
My favorite way to wire these is for 4th gear only lock up. No computer or vacuum switches needed for this method.
To do 4th gear only, leave the 2 prong pulse swith alone, as it serves as a pipe plug.
Replace the single prong switch that you currently have(normally closed) with the normally open type. I have the gm part number handy and can look it up if you like.
Make sure terminal A has 12 volt ignition power and leave that wire alone. Cut the ground wire on the solenoid and run it directly to the 4the only (normally open) switch in the v/b. That is all there is to it.
There are many aftermarket lock up kits out there, and I do not like any of them. Toggle switch arrangements become a pain in the nuts very quickly. Vacuum arrangements suck as well.
To do 4th gear only, leave the 2 prong pulse swith alone, as it serves as a pipe plug.
Replace the single prong switch that you currently have(normally closed) with the normally open type. I have the gm part number handy and can look it up if you like.
Make sure terminal A has 12 volt ignition power and leave that wire alone. Cut the ground wire on the solenoid and run it directly to the 4the only (normally open) switch in the v/b. That is all there is to it.
There are many aftermarket lock up kits out there, and I do not like any of them. Toggle switch arrangements become a pain in the nuts very quickly. Vacuum arrangements suck as well.
This is the arrangement I did on my buddies 84 corvette.
Thread Starter
Pro
Joined: Jul 2006
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From: chiefland fl
got ya, i probrably wont have any vacuum any wayz with a big cam LOL, thanks guys, INVALUABLE INFO! should be able to find the P/N easily, 
if the tranny doesnt last long, better get me one ready Pete!
if the tranny doesnt last long, better get me one ready Pete!
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Race Director
Joined: Feb 2004
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The switch you need is available through gm and ac delco.
The part number is the same for both
8642473
They are $12 or less
The 4th gear only arrangement is popular because it works well, and does not require any computer to work. Street rod guys love it.
Rest easy. I have a bitchen trans on the stand now. I hope yours holds up, but if not, I have you covered.....Pete
The part number is the same for both
8642473
They are $12 or less
The 4th gear only arrangement is popular because it works well, and does not require any computer to work. Street rod guys love it.
Rest easy. I have a bitchen trans on the stand now. I hope yours holds up, but if not, I have you covered.....Pete
