We use rechargeable LED Light Tubes to inspect wood for flaws while building high end custom cabinetry. These lights have 5 settings (low, med, high, sos, strobe). Each press of the power button toggles the light through the modes. We just need "High" and "Off". Can it be rewired so one power button press turns it on High, and the next press is Off?

Link to image gallery for Hi Res versions. One end cap is the power button, other end cap is the circuit board. I only captured one side of the circuit controller board but can take is apart again if needed. I could not get wiring diagrams for these Letour LT-LT120 lights. The sole distributor was no help.

You often miss the toggle for "High" and have to cycle through all the modes again, and miss it again, or again. It's infuriating.

 

The short answer is "no".

If You have to ask the question, then You probably don'y have the experience
necessary to make your own Control-Board or modify the existing one.

Pick a different Flashlight, there are thousands to choose from.
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The short answer is "no".
If You have to ask the question, then You probably don'y have the experience
necessary to make your own Control-Board or modify the existing one.
Pick a different Flashlight, there are thousands to choose from.

Granted, it's been 38 years since I graduated MTU in EEE. The question was to guide if I approach shops in Phoenix that have the time or skills to modify all 17. I don't. Also, there are not "thousands" to choose from. Few tubes provide the Lumens necessary, the battery longevity to last days, or durable. Tubes for photography require even more steps, are fragile, and cost prohibitive at $500-900 each.

 

If You really want to go for it,
you'll need to supply all of the specifications for the Hardware that You have to work with,
including the wiring scheme used to connect all the LEDs to each other,
( Series/Parallel configuration, and any Series-Resistors that may be used,
and exactly what Chips are being used,
( Switching vs Current-Regulation vs Single-Chip for all functions ) ),
and the measured amount of Regulated-Current being supplied to the LEDs.
And, ( I almost forgot ), the Charging-Method for the Batteries, and Battery Nominal-Voltage,
and how much space will be available for the installation of a new PCB.

With all of the above information put into the form of a well-labeled Schematic,
creating a very efficient Switch-Mode-Current-Regulator should be a relatively simple task.

Also, Replacing the Momentary-Push-Button-Switch with a
Push-On/Push-Off-Switch, or a Toggle-Switch, will make things much easier.
But, it might be that having to manually hold-down the Push-Button-Switch
is not a negative issue with your particular type of usage,
and may actually help to extend the time between Battery-Charges.
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These lights have 5 settings (low, med, high, sos, strobe). Each press of the power button toggles the light through the modes. We just need "High" and "Off". Can it be rewired so one power button press turns it on High, and the next press is Off?

Trying to redo the circuit may be difficult if you have no info on it.

It would be a bit of a kludge, but you could add an oscillator/counter that would generate 3 pulses to a relay/transistor every time you pushed the button.
The relay/transistor replaces the button connection to the board.

There are actually six settings, including Off, with the High setting conveniently in the middle.
Thus one button push from the Off state would give the sequence low-medium-high, and the next push, the sequence sos-stobe-off.
You would need to add a single-step push-button to initially set the sequence to start in the proper order (or in case you wanted to use one of the other setting).

If that sounds like something you might want to try, I can help with the details.
It would require a couple of ICs, a transistor (and possibly a relay), and a few passive parts, which could be built on a small perf-board, or perhaps make a PCB if you are going to modify 17 of them.
The circuit would be designed to take no quiescent power.

The first information I would need, is to have you measure the voltage from both the power button terminals to the minus terminal of the battery, with the button open and with the button pushed.
That will determine whether a relay is required to emulate the PB closure.