Torque Converter Lock Up Switch

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TC Lock Up Switch

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Original Write Up By THURENfab.

So I wanted a switch to lockup the torque conveter clutch, but I wanted this switch in a VERY easy spot to toggle it off and on. I took the wheel/airbag apart last week and found an extra port on the clockspring, so I decided to try and use that port for my switch connection.. Working out good so far!!

I don't know what this connection is supposed to be for, so some trucks may be using it, or not have it at all... Not sure..

Step one.... PULL BOTH BATTERY GROUNDS!!!! AND LET SIT FOR A MINIMUM OF 2 MINUTES TO ENSURE COMPACITORS ARE EMPTY Unless you want the airbag to blow in your face.

Parts used... This switch has a VERY light feel so a slight nudge will lock/unlock..

Wiring up an LED to come on when the TC is locked..

Im no wiring pro, so I stacked two of the 680ohm resistors..


On....


One of the torx screws is WAY up there, so I just used a tight fitting allen..

Slide the tilt handle to the rear of the truck..



Pop open the panel under the column and remove it by pulling the two screws on the bottom...



10MM socket to remove the 2 airbag screws behind the wheel..

Three connection for the airbag..



Extra port we'll be using..




Extra plug just sitting there under the column..

Un-tape and follow the wires back about 10 inches.. Cut off and stub..




Two dead slots in the clockspring plug we'll use..



Extra dead plug that was removed. Unlatch the back cover, and push and twist a heavy paperclip.. You will feel a very distinct release when it's ready to come out.

Close up of the terminal..


Take two of the cut leads and make a switch harness..

Close up of the harness end..



Switch installed.. (NOTE: Install your switch as close to the center metal as possible. Mine rubs the cruise switch once re-installed)


Plugged in and tied to the rest of the wires..

Remaining two leads plugged into the extra ports in the clockspring plug..

Two wires ready for final hookup..



Ready for action..


VERY slight touch on the switch and my OHM meter zeros out. This instal is going to be using a latching relay to operate the on-LED, and control the converter. You would NOT want to use this switch technique using a direct connection as the clockspring probably can not support the direct electrical load.

More to come when the special little relay comes in!!
Stay tuned..

--Iker42 22:15, 9 July 2007 (EDT)