cboyd

Hi guys
Just in the process of installing my TCI lock-up kit in the 2004R transmission. This transmission is a late 80's model. Used the cruise control connector on the back of the brake switch, console switch to disable the lock-up during city driving, and the included vacuum switch. Bench tested the set up and everything works. Solenoid wiring is complete. Thing is, the kit came with a 2 terminal 4th gear pressure switch with a 1/8" male NPT. When I went to remove my pressure switch I noted that the thing wasn't screwed in like the one that came in the kit. It has a bracket that is bolted to the valve body and has a small tube that connects it to the valve body. There is a NPT plug next to the pressure switch.
Question: (1) If I already have a 2 terminal pressure switch, do I need to use the one that came in the kit.
(2) If I have to use the supplied pressure switch, do I remove the NPT plug next to the switch and install the new switch there. Thanks again guys, any help would be appreciated.

'75

Do you know if the switch you already have is normally open or closed? Here is a pic of an 88 Monte Carlo SS valve body, the 4th gear pressure switch is a single terminal normally closed switch, in fact all the 2004r switches I have seen are normally closed. Best to replace it with the one from the kit, then you know for sure. The switch in the pic is in the 4th gear port.

'75

With a 2 wire switch there are 2 different ways you can wire it in. Either the power wire coming in can connect to one side and then connect the positive side of the lock up solenoid to the other terminal. Or run the power wire directly to the positive side on the lock up solenoid and then run the negative side of the solenoid through the pressure switch and the other terminal of the pressure switch gets grounded.
I usually just use a single terminal switch from a 700r4, its normally open, I hook it up to the ground side of the solenoid.

In the picture above, there is an 1/8 inch pipe plug in the right end of the valve body, it sees pressure in 3rd as well as 4th. If you put the switch there, you would have lock up in both 3rd and 4th. Not all 2004r valve bodies have the 3rd/4th port drilled and plugged.

cboyd

The problem I is my pressure switch is not installed like that. I will try and get a pic and post it.
Thanks
Clyde

cboyd

The way my kit is designed, the pressure switch closes the ground on my kit, but if I remember correctly with the original wiring it closed the 12v. The solenoid was grounded internal in the transmission. Again, I will run to the shed to try and get a pic of my pressure switch. thanks.

cboyd

As u can see in the pic my pressure switch is attached to the valve body by a small tube. about 2" to the left of the pressure switvh is the 1/8" plug I mentioned. No way I can screw that pressure switch into the valve body. I guess I can put the meter across the 2 terminals and if the circuit is open I should be able to use the existing pressure switch. I messaged TCI but got no response. Anyway guys if anyone has any suggestions it would be great. Thanks again.

cboyd

The way my kit is designed, the pressure switch closes the ground on my kit, but if I remember correctly with the original wiring it closed the 12v. The solenoid was grounded internal in the transmission. Again, I will run to the shed to try and get a pic of my pressure switch. thanks.

'75

i found a pic of one with the switch you have, it's in my manual, listed as an 87 year valve body, probably a caprice or delta 88. It says switch, pressure 4-3. Presumably it's normally open. I notice on your pic, looks like the new solenoid is in wrong, the angled corner should be on the other side so as not to interfere with the TV lever.

This pic is from a BRF valve body, Buick Regal turbo.

cboyd

Thanks for that info, you just saved me a lot of trouble. I installed the solenoid last night, but will switch it this morning. Great catch. So if this switch is normally open, I should be able to use it in this lock-up situation. I also noticed a small hole in the tubing right at the pressure switch. Is this factory or do I have another issue. Thanks again.
Clyde

cboyd

http://api.viglink.com/api/click?for...0-4R%20diagram.

I just found this on the another forum. Not sure if copying the URL will work, but the drawing shows my set up with the 4-3 pressure switch and the plug next to it. The lower drawing shows the 4th clutch switch where the plug is. The write up states:
"Yes you can take out the plug and put in the 4th gear psi switch. You could plug the 4/3 pulse switch or just leave it there unwired."

These may help you out a bit http://www.montecarloss.com/TCC_Solenoid.html http://www.aros.net/~rbuck/tech/4thgear.html

cboyd

Well more problems arise: had the whole system installed and when I tested the system I kept blowing the fuse. Did a bunch of checks to confirm I didn't have a short in my wiring and everything was good. Check the resistance across the coil on the solenoid and got a dead short. It is my understanding that I should have about 25 ohms across the coil. Is this correct? When I put power to the solenoid you can hear it click. Is it safe to say that my solenoid is faulty? thanks

'75

The solenoid is biased, when hooked up backwards it will give a direct short.

cboyd

O.K, I take it black is ground and white is power? Either way, putting the meter across it should give me around 25 ohms, not a dead short???

'75

Yes, black to ground. I just checked 2 used solenoids and both read .016 k ohms, checking both ways.

cboyd

guess it's a new solenoid. $19.00US on line, $89.00 cdn at the local parts store.
C