Perun V2 MOSFET issues in receiver. HELP PLEASE!

Hi all, new to the gel blaster scene and in desperate need of help. Finished wiring up my Perun V2 to the FB 4.0 gearbox for my LDT HK416 V3 from monkey mods and all was working fine outside of the receiver (allows me to enter programming mode and edit settings) but once installed into the receiver can not get it to enter programming mode at all. Am i doing something wrong here?

So how did you set it up outside of the receiver? You need to use the fire select to do it


so fire select plate was in place on the gearbox. the unit works perfectly when i slide the plate back and fourth with my hand but once i install the gearbox back into the receiver it fails to enter programming mode (sometimes enters from single fire)

could it be the actual select fire switch on the receiver that’s causing the issue? I’ve got the white sticker with thin black line on the plate atm. i was using the solid white sticker but that didn’t seem to do the trick previously.

You can tell by looking which sticker you need, in safe and semi the sensor is uncovered and when in auto it is covered.
I have never needed to use anything other than the full sticker so far

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hmmm… ill try the full sticker again and see what happens. i just don’t understand how it can work in the gearbox outside the receiver but doesn’t work inside? any insight? thanks for all your help btw its greatly appreciated.

Maybe the fire select switch is not moving it as far as you can by hand


If you removed the fire select make sure you put it back correctly

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haven’t touched the fire select switch on the receiver. just the plate on the gearbox. i think you may be right about the sticker. i was originally running the fighting bro clear selector plate but switched back to the OEM plate that came with the HK and that’s when i decided to change the sticker to the thin line. when the FB plate was on the issue was reversed (auto would go into programming but semi wouldn’t) now semi occasionally goes into programming mode but auto doesn’t ahhh :tired_face: