JG Aug A3 problem

[DryGoldFish]

Hey all,

Yesterday I got the JG Aug A3. I decided to shoot with a 9.6v battery I had (fully charged) and it shot about 10 meters.
I thought it was really odd and decided to take the gearbox out of the gun. While doing this the cable from mosfet chip itself to the connector on the gearbox came lose (so the gun stopped shooting)
I connected the battery again, held the cable onto the connector and it shot again. I went to my dad to ask his soldering iron and explained what has to be done.
However, when I connected the battery this time, the gun kept shooting full auto without holding the trigger (so I took out the battery asap)

Did I fried my fet?
I really want to have this gun working.

Thanks in advance,

Chris

[Kos-Mos]

Fried your FET.
Your dad might not have the "skillset" or tools to repair sensitive electronics. Sounds like a overheated FET chip.

[DryGoldFish]

Well we never got to the soldering part
I was thinking about buying the PicoSSR mosfet to replace it.
Would it do the trick?

Also, I was wondering why the FET fried, the gun is brand new :/

[ccyg8774]

MOSFET is sensitive to heat. It can be soldered, but it have to be done VERY quickly, which is diffcult...
It is not fried at first, just a bad soldering joint coming loose. Your soldering fried it.

[DryGoldFish]

Like I said in my reply: We never got to the soldering part. The aug comes with a stock mosfet.

[ccyg8774]

So you are holding the loose cable to where it should be, and it still fires in full auto without holding the trigger?

[DryGoldFish]

No, now it shoots full auto when I connect the battery. I think it's weird because it's the cable that starts from the mosfet that came loose.

[Stealth]

Re-solder the wire as it was from the factory, then inspect the entire wire harness for any shorts. I know the AUG wiring harness just wraps around the box in odd ways so you may have some exposed wiring/shorts there when you pulled the box out.

For what it's worth, not all FETs are created equal and I personally would not trust an ACM factory FET.

[ccyg8774]

MOSFET have two types of wire, the high current ones connect the battery and the moter, and the low current ones for the trigger. If the low current ones are broken, loose, disconnected or shorted, different weird things could happen depends on the design of the MOSFET, include firing without pulling the trigger. That happened once to one of my gun with ASCU-II MOSFET.

[DryGoldFish]

So this is how my gearbox and mosfet look like.
I drew a red line on how it should be soldered.
So my gun should fire back to normal when I connect the wire to the connector?

Also, where I drew the circle, the pins tend to disconnect. Should I tape some electrical tape around it to keep it togheter?

[ThunderCactus]

That is some sloppy ass soldering on the side of that mechbox lol
If those solder globs are arcing through the mechbox, that could be causing the gun to shoot full auto as well.

Since all those wires are on quick connects, disconnect the two thin wires (trigger wires) and test for continuity with a multimeter. If there's continuity without you pulling the trigger, then the problem is not the mosfet, you have a short somewhere.

Also, is that a SQUARE cylinder port? That's ridiculous lol

[DryGoldFish]

Well it's a JG, so I guess I got what a paid for? (307 CAD)
Hmm, is there a way to test it without a multimeter? My dad is a welder, so I guess he doens't have that.

[ThunderCactus]

use a 9v and a small light if you have them
if you don't have a light, you can use the motor on the gun, just take it out of the mechbox first otherwise nothing will happen lol
this is only for testing, so you won't be hurting anything. The trigger wires should still be able to turn the motor over with a 9v.

[DryGoldFish]

Okay, just connected my 9.6v battery for a few seconds and the fet was REALLY hot. I literally screamed when I touched it. I guess I have to order a new mosfet and wire it.

[ccyg8774]

......
I will never buy a JG AUG after I read this...