CONVOY M3 DRIVER PROBLEM

Flashlight Modding and DIY Parts
1

Good morning. I have a Convoy M3 flashlight and I have a problem with the modes. Turbo mode does not work, I have already tested with fully charged 18650 and 26650 batteries. Sometimes turbo mode works but it doesn’t last long (max 40 s). The high mode works only for a time, 5-10 min and then it does not let you put that mode anymore, only the medium or low mode, and sometimes I cannot put even the lowest modes, still having 3.7V in the battery. I would appreciate any help. Thanks!
PD: The driver has already get changed by another one I bought in Banggood ( Konvoi 4 Modi XHP70.2 Treiber für Konvoi M3 Taschenlampenzubehör Sale - Banggood Deutschland-arrival notice-arrival notice )
PD 2: I would also appreciate if someone knows how to remove the overheat protection since I want the turbo mode to operate whenever I want and since the flashlight is mounted on a bicycle it will not have any temperature problem
Video: https://drive.google.com/file/d/16E_gQQQ7dj77nEVchpdCgBtxCllATguu/view?usp=sharing

Solved (temperature problem):
Tutorial: [TUTORIAL] CONVOY M3 DRIVER REMOVE OVERHEATING PROTECTION | QUITAR PROTECCIÓN SOBRECALENTAMIENTO

2

From the Convoy Store: Link

“Requires battery type: IMR26650 or IMR18650 (direct current must be greater than 11A)”
So what battery are you using? Make and model. Not all batteries are equal. At 3.7 volt, the battery is 3/4 depleted of power and will not give boosted output. This is a 6 Volt LED, the circuit boosts the voltage and consequently the current drawn on the battery.

Also, temperature sensor built-in CPU, can’t be changed or over-written by the user.

Edited (20.08.05) - From Yokiamy Convoy 17/22 mm SST40 Driver temperature protection removal

Thanks for the info.

3

Hi, the batteries are 186650 Panasonic and 26650 Liitokala 5000mAh (5.3mAh measured. From 4.2V to 3V)

4

Check spring bypass on both end(driver and tail side).Makesure the bypass wire soldered properly.

5

Try refer to this thread,post no 41

this thread

6

sounds like a battery problem.

The Convoy M3 is using a boost driver which only allows Turbo to operate until the battery drops to 3.7 volts on load.

If you want Turbo to be always an option then you need a flashlight that uses a 3 volt led.

I use a Samsung 40T in my M3 and only get about 10 min Turbo until it’s no longer available, this is normal for a boost driver powering a 6v led

7

Hi, I finally removed the temperature protection thanks to @jojosupir. I will post a Tutorial for the people who dont know hot to remove it.

8

Is that NTC pointed out in the other thread really for the temp? No one ever confirmed it so I never thought anymore of it.

9

Simon has said that the M3 is not using an NTC to regulate temperature

There’ll be an upgraded M3 coming soon that has an NTC and has USB C Charging

10

Hi @PiercingTheDarkness,actually yes, this NTC regulates the temperature because when you short the two pins the resistance is almost zero and the flashlight dont turn on even on the moonlight mode. And when you dont short the pins, it keeps on a very long time in turbo mode. Even more, I plugged in the flashlight in a constant 4.2V 5A power supply and it long 20 minutes because I stopped the test, the temperature was quite high, but if it was cooled with a fan I’m sure it will long hours. At least, in my M3 version the NTC was the component I removed

11

I'm really tempted to desolder mine, too. But I would feel relieved if someone can confirm this component's only purpose is to control the stepdown temperature and nothing else. ;-)

12

Today, I made my very first attempts with a soldering iron. Fortunately, I did not kill the driver as I felt a bit nervous. I managed to desolder the NTC resistor of my Convoy M3 (XHP70.2 3.000K). Now, this light is much better, not stepping down way too early.

Thanks a lot for your great how-to manual eliasklk_04.

13

Great @Lux-Perpetua ! I’m glad to hear that it has worked for you!
Now I am looking for how to reduce the low voltage protection because I do not know why my flashlight does not turn on more when the battery reaches 3.7V - 3.6V, even in the moonlight mode

14

LVP kicks in at 3.7V already?! :O

Did this happen after you desoldered the NTC resistor or already before? Can this problem be related to removing the NTC resistor?

However, I will now check my M3 what it does if the battery gets drained below 3.7V.

15

I ques better to use higher value NTC instead of removing…

16

Regarding the NTC resistor and the LVP at 3.7 volts, check the original post.

eliaskik is having an issue with premature stepdown. The thermal part is taken for.
He would have a problem at 3.7 volts and lower. Wouldn’t know if all modes or turbo / high (the latter would make sense being a step-up drver for a 6 volt emitter.)

17

Thank you Sidney Stratton. I paid more attention to his other thread where he described the NTC removal, so I totally forgot about his LVP problem in the OP of this thread.

18

Have you tested 3.7V cutoff after ntc removal? Does it influence cutoff at other modes to 3,7V or they are not affected?

19

Pretty certain it was just Turbo at 3.7v. You’d get another issue when High needs to step down at a lower voltage and then the same at med.

If you manually step it down a mode when it flashes you can use it normally

20

Ok so manul stepdown solves it for other modes, thats ok for me as long it does not cut of at 3.7V for all modes, so off to removing the ntc. Thanks