Lockup switches. Open or closed?

HighMileage

Albany,NY
Joined
Jul 24, 2010
Hey gang,

I've got no lockup but I'm getting the command as per my powerlogger.

This is a replacement tranny for the replacement tranny. The lockup worked in replacement #1. Unfortunately replacement #1 turned into a Slushbox after 100 miles or so.

The lockup hasn't worked in #2 since installation. Same converter as #1.

I'm gonna check the switches. Maybe they put the wrong ones in. I did notice that the plug on the 3rd gear switch was loose fitting.

I'm thinking of not plugging the 3rd gear switch in.

Are the switches supposed to ohm-out open or closed?

Thanks!
 
The stock 200-4r 3rd & 4th gear switches are normally closed. They open once the transmission shifts into that gear, with the 3rd gear switch also being open when the trans is in 4th.

RemoveBeforeFlight
 
Hey gang,

I've got no lockup but I'm getting the command as per my powerlogger.

This is a replacement tranny for the replacement tranny. The lockup worked in replacement #1. Unfortunately replacement #1 turned into a Slushbox after 100 miles or so.

The lockup hasn't worked in #2 since installation. Same converter as #1.

I'm gonna check the switches. Maybe they put the wrong ones in. I did notice that the plug on the 3rd gear switch was loose fitting.

I'm thinking of not plugging the 3rd gear switch in.

Are the switches supposed to ohm-out open or closed?

Thanks!

On the 4 pin wire connector Pin A purple wire is the +12 VDC that comes from the brake light switch and goes to the TCC solenoid. Pin D Tan/Black wire is the ground side of the TCC solenoid and goes to a driver in the ecm that is controlled by your chip parameters that must be met before issuing the TCC lock-up command.

You should be able to measure resistance accross the TCC coil....20 or so ohms with the four wire connector removed, figure out which 2 wire ports the tan/black and purple wire goes to and measure there.
If you have a manual lock up switch you are usually grounding the tan/black wire to force lock up via the F diagnostic port.

The 3rd and 4th gear pressure switches do not directly lock the converter.....they are used as input status indicators that report to the ecm IF the trans is in 3rd or fourth and at some point with all criteria met the ecm will issue the lock up command......I have gotten chips where the lock up command had been left out inadvertently.

Since your logger is showing the command{ This would be the ground side} I would make sure that the +12 vdc side is good and measure the coil resistance.
If you PM me your number I will take a pic of the wiring page for the trans and send it back to you.
HTH
 
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Well,the TCC solenoid isn't gonna do much with it hanging out of the bottom of the tranny,now is it?

I just pulled the filter down. The solenoid is just swinging in the breeze.

Question: Does the solenoid attach under those nuts,or does another set of nuts hold it on? If I do this wrong there is gonna be a depth issue from the looks of things.

I can't believe this..

image.jpeg
 
...and another thing:

Do new solenoids have this nut imprint on them? ....or did they throw in a used solenoid?

image.png
 
That is a replacement solenoid but it looks like it has been installed/used at one time by looking at the witness marks from the nuts. I assume you didn't find the nuts in the pan. Bolt it in and see what happens or just buy a new one and install it. They are pretty cheap.
 
doesn't that create some sort of a massive internal leak if that solenoid isn't installed?
 
doesn't that create some sort of a massive internal leak if that solenoid isn't installed?

Well,I put about 500 miles on it that way. Maybe not having it in there caused damage by starving part of the tranny on some way?

There was just a tiny bit of black haze in the middle of the pan.

The pan is up and it's ready for fluid.

Hopefully not having that solenoid in there didn't shorten this trannys life.
 
The solenoid valve is normally open until it closes to move the converter lockup shuttle valve in the pump. It won't hurt anything if it has fallen out it just won't lock the converter.
 
I would get a pressure gauge on it before going any further.


Sent from my iPhone using Tapatalk
 
Wow, did you buy this from a Buick vendor?

The tranny is not from a vendor here,but it is not from a Joe-schmoe neighborhood shop,either.

I can't say any more than that without risking retaliation when it comes to needing warantee work.

I'm about to take a test drive. Hopefully the lockup works now.
 
Well,the lockup works now. The shifting is getting less harsh,too. I guess they are supposed to soften just a little once things break in.

Next is to send the chip back to Eric and have him change a few things and get rid of the 3rd gear lockup.

All is well in TCC lockup land.

I just wish I could share my almost 2 year nightmare ordeal about the tranny people I dealt with.

Btw,it's not Dave Huseck. I haven't dealt with him before. Maybe I should have.
 
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