Need advice with Mountain Electronics driver - MTN17DDm-NUV

Does anyone know what could be the cause of this?

Unable to get Convoy S2+ to work with battery inserted.
This is what works on CREE XP-L HI V3 1A LED on Noctigon 16mm MCPCB and MTN17DDm-NUV:

  1. able to get led to light very bright when direct wiring tip of positive spring bypass and negative soldered point on mcpcb
  2. normal audible continuity sound can be heard when touching tip of positive spring bypass and no anno side of middle tube
  3. normal audible continuity sound can be heard when I insert battery and touch tip of negative battery end and no anno side of middle tube

What does not work:

  1. unable to get led to light up when I short battery and no anno side of middle tube
  2. no audible continuity when I touch tip of positive spring bypass and pill

This is the driver info I have:
FET + 7135 Driver - 17mm - MTN-17DDm

  • Firmware: Electronic Switch Standard
  • Turbo Timer: Bistro/D4/Cresc. (Temp sensor; no timer)
  • Wires + Spring Option: Complete | Wires + Bypassed spring
  • Model: MTN17DDm-NUV

Have soldered the driver onto the mcpcb 3 times, each time with same result.
What I can add is that:

  1. had to lightly sand middle tube to get continuity to work using 320 grit sandpaper
  2. the reflector is touching the solder points. Have covered with kapton tape.

Hi LycheeS! Welcome to BLF!

Looking to what you said - and I may be wrong - your problem is related to the type of firmware installed in the driver and its incompatibility with the flashlight (or vice-versa)

You have a Convoy S2+ flashlight which works with mechanical switches (reverse clicky switch or forward clicky switch), while your driver has installed a firmware designed to be used in electronic switch flashlights (like the Emisar D4 or others).

So, unless I’m missing something important, your flashlight won’t be able to use this driver since they are not compatible.
You can choose a ramping firmware to use in a Convoy S2 but that will not be “Electronic Switch Standard” nor “D4 UI V2 (E-switch)”, it will be “Crescendo”, that is designed to be used in flashlights using mechanical switches.

I hope it helps! :+1:

Agreed. You need a driver with standard firmware for mechanical switch input. The e-switch firmware has the mcu waiting for a signal from a different input point (switch)…the mechanical tail switch is only connecting or cutting power, so half presses as usual just cut power without the mcu interpreting an instruction to do something.

I don’t think there’s any creative way to get around this in the S2+ host since there’s almost no room to add things even if you wanted to drill holes in it. :slight_smile:

Is it possible to flash the correct firmware?

Yes, that’s what MTN does to the drivers. But you’ll need the proper hard/software to do it. At least the firmware is free thanks to ToyKeeper!

Here’s a good post about flashing firmware: Need help with firmware flashing

Unless you want to start flashing firmware with multiple flashlights, it may not be worth your time and costs to do so. But if you’re up for a new learning opportunity, good luck to you.

Maybe you could send it back to MTN to swap out the firmware, or it may just be cheaper to buy a new driver.

Appreciate the responses. Has been a big learning experience so far with lots more to learn. Will post updates.