no voltage when pedal depressed.

A SPST relay behind the dash could have it's coil powered by switched hot from the key.

The brake-switched ground would connect to the relay coil through the switch of the relay and a momentary contact switch wired parallel on the dash.

Once the momentary contact switch closes, the relay latches on until the brake pedal switch interrupts ground and de-energizes the coil.

The switched ground out to the original relay would be cut and wired to the (-) side of the under dash relay coil.

An indicator light could be grounded to the same terminal.

I get the van up to speed, push the button, both relays energize and the light goes on.

I touch the brake, they all go off until I press the button again.

It might be wise to somehow incorporate power from the oil pressure switch so that TC isn't locked after an engine stall. (If I stalled on the highway, I think the TCLU would make me lose momentum quickly and diminish my capacity to roll to the shoulder).

Then again, rolling locked up would keep the engine turning, oil pressure up switch closed, and TC locked.

I guess I could just try to remember to tap brake pedal when I stall.

I thought lock up torque converter unlocks and unlocks at a pre set rpm. Or, have I lost track of thread and now discussing a shade-tree fix devoid of factory controls?

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67' Dart GT Convertible; the old Chrysler Corp.
82' LeBaron Convertible; the new Chrysler Corp
07' 300 C AWD; Now by Fiat, the old new Chrysler LLC

My van had 'computer' controlled TCLU.

I removed the 'computer.'

I had disconnected the TCLU wiring when it was behaving badly as part of a larger problem solved by that removal.

I'd like to have the TC lockup on demand, which is a mini project I will do as part of a larger project of removing wire I don't need and making sure the wires I do need are in good working order.