DIY Torque Converter Lockup Switch

chevyburnout1

Fixing it till it breaks
Aug 25, 2008
2,368
1
38
Berthoud, CO
I figured I would try out something here and see what you all think. I love dealing with 12volt wiring and decided to try my take on a homemade torque converter lock up switch. Nothing fancy, just a switch that forces lock and unlock and that is it.

Pardon the primitive drawing but this is what I was coming up with based on my little knowledge of how the Allison converter clutch circuit works. In the drawing I have kind of generalized what the PWM Module represents as I feel that will be a more researched, trial-and-error sort of setup later on if this does work. Just trying to find a different solution for those more 'do-it-your-self' types that don't want to buy a lockup box.

In theory I believe this setup should not set any TCC CIRCUIT codes, however the use of basic mechanical relays may not be of best nature. I also have no idea what the TCM will think in regards to the codes "P0741-Torque Converter Stuck off" and "P0742-Torque Converter Stuck On".

I would love to hear any critisizm on this from everyone. Let me know if I'm crazy or if I have overlooked something, or if I should actually take it to the next level and try this out.

Note: I am in no way trying to step on anyone's toes that create these lockup boxes for the Dmax community nor did I 'reverse engineer' any persons product. This is just a theory that has popped in my head that I would like to share.

 

duratothemax

<--- slippery roads
Aug 28, 2006
7,139
10
0
Wyoming
That should work fine. The only issue is depending on what PWM module you use, you wont have any smooth PWM ramp-up, so lockup will be very harsh. Make sure you get the PWM frequency correct too.
 

Balindir

Rod shortning in progress
Jul 30, 2012
364
0
16
South Central, Pa
What IC would you use for your PWM? I was looking into the 555... but I don't have nearly enough knowledge to make a call as far as that is concerned...
 

chevyburnout1

Fixing it till it breaks
Aug 25, 2008
2,368
1
38
Berthoud, CO
That should work fine. The only issue is depending on what PWM module you use, you wont have any smooth PWM ramp-up, so lockup will be very harsh. Make sure you get the PWM frequency correct too.

Thanks for your input Ben. Like I said the PWM module was just generic in the schematic right now as I was focused on the wiring, but good to know that I'm in the right direction. I'll dive into this further.
 

chevyburnout1

Fixing it till it breaks
Aug 25, 2008
2,368
1
38
Berthoud, CO
What IC would you use for your PWM? I was looking into the 555... but I don't have nearly enough knowledge to make a call as far as that is concerned...

To tell you the truth I don't know much about microprocessors to even tell you where I would begin lol. I've been doing a lot of research and this 'simple switch' setup just does not seem to be feasible. I just caught another issue. The unlock part was what I was more interested in right now as my truck doesn't have enough fuel for lockup issues. But how my diagram is setup now if I go from the forced unlock position back to "Off", or factory control, there will be no PWM ramp up and the lock will be harsh....

Lockup boxes are sounding better and better after all this haha