G&G Wiring Problem!

[chirpy456]

Ok, this is going to be a long one so stay tuned!

I bought a G&G CM16 Predator around mid August. I used it for about a week. One time while using it I ran it on full auto with an 11.1 lipo (15-25c). I stopped and switched back to semi. It sounded like my gearbox was locked or something. I brought my gun back inside and I tried adjusting the motor hight (no idea why) but I looked under my pistol grip and saw sparks flying out. The next time I tried doing anything the 25 amp fuse popped.

I brought my gun to my local shop not knowing anything that was wrong with it. They just said my fuse was popped and I had to get a new one. I go to Walmart and get a variety of new fuses. I come back home install the new 25 amp fuse and as soon as I plugged in the battery, pop, the fuse popped immediately. I waited for a while to go back to the store. I went back to the store and of course they were closed.

I come back home. I finally open up my motor plate, (had stripped hex screws, took me hours haha), and noticed my red brush spring was burned/melted off in two. I located both pieces and take them out. I noticed my red wire was resting on my pistol grip a little. It melted some plastic off. Maybe short? I take the motor out knowing I need a new brush spring (haven't had the time to go get a new one). I then decide to see if that plastic melt caused a short. I plugged in a 20 amp fuse and made sure no wire was touching the pistol grip(the motor was not plugged in), I put in my 11.1 lipo in and again, pop, the fuse pops immediately.

I become so frustrated. I then do some research on my ETU (in most modern G&G Rifles) and people say that is is super unreliable and etc. Is my problem the mosfet? (I noticed that some of the natal has now turned brown, if that's normal or not at all). What's causing my fuses to pop? I'm getting really impatient and I haven't been able to play airsoft for months. Anything would help guys, thank you!!

 

[Sitting Duck]

Dreaded ETU

take it back to the shop or the retailer where you bought it from

the mosfet unit inside the stock tube is crap and mine blew a fuse then another

it doesn't take much even if sort out a short or overload - the unit in the tube craps out and it is f*cked

(my fuse started to blow when I replaced the motor to a much more powerful one and kept blowing after that)

in the end I ripped my ETU out completely and went back to conventional trigger and my own "normal" mosfet

but it is a little involved as you need a new trigger switch, new selector plate and rewire with a 3034 or firestorm mosfet

(lost 3rnd burst but that was just a gimmick imho)

Honestly they are flawed - some run fine for ages but others have had problems and often people have had to run with at least 9.6v or 11.1v

My best bit of advice take it back try to get it swapped over or part ex on a Krytac

or if you know a tech rip the f*cking ETU out and go old school

yes you could replace or get the ETU mosfet unit replaced as long as you have fixed the shorting out in the motor plate

(try a few pieces of electricians tape on the motor plate itself to insulate it better and heatshrink tubing on connectors)

it is up to you but you have a gun that has higher than average lemon rating or prone to some issues

there was some batches of G&G ETU guns that had iffy mosfet units, they was supposed to fix/replace them

but I wasn't impressed with the reliability or build quality of the ETU electronics in G&G's latest guns

I'd say the 3rnd burst mosfet module in the stock tube is boned like mine was (kept blowing fuses)

sorry to hear your bad luck - hope you can get it sorted

 

[Shizbazki]

Hi

I think the best person to help you on this is Sitting Duck as he appears to have all the knowledge on G&Gs and their notorious ETU MOSFETS but will also try and help you diagnose the problem if I can, I have since moved on from AEGs to P* as their unreliability caused me no end of frustration.

You have not mentioned if you tried running the motor by itself outside of the gearbox and just pulling the trigger to see if the motor just runs smoothly, most AEG motors do spark up when current is applied to them and will do that for every trigger contact.

I recommend you plug in another fuse, remove the motor from the pistol grip, ensuring that the motor wires are connected, hold on to the motor and just pull the trigger, normally in an standard AEG the motor will just run until you let go of the trigger. Yes there may be some sparks and the motor will start to feel warm (not burning you but do wear gloves).

If the motor runs normally when the trigger is pulled and the stops normally when it is released then the ETU, motor, fuse and wiring is not the problem, the problem is a bit more complicated in that the reason your fuse is popping is that the gearbox is locking up.

If the Fuse pops then the ETU is likely to be at fault, G&G invented a new fandagled ETU/MOSFET configuration that needs an 11.1v LiPo but can’t handle 11.1v LiPos, I know figures.

You could skip all this crap and just get the following items, probably cheaper in the long run in terms of money, effort and time:

Get a proper MOSFET such as a GATE PICO AAB (used to be my favourite MOSFET when I had AEGs) http://airsoftzone.co.uk/parts/internal-parts/mosfets/picoaab-3rd-generation-active-breaking-mosfet-gate-electronics or any of GATEs MOSFETS as they are pretty good and fairly cost effective: http://gatee.eu

Get or buy a standard V2 gearbox trigger contacts some come with wires attached already: http://airsoftzone.co.uk/parts/internal-parts/gearbox-parts/ver-ii-switch-assembly-for-rear-wired-gearbox-gnp

Get or Buy some 16AWG Silver wire (don’t use the silicone crap): http://airsoftzone.co.uk/parts/internal-parts/gearbox-parts/silver-plated-low-resistance-wire-made-in-japan-ultimate-asg

Get or buy some decent motor spade connectors: http://airsoftzone.co.uk/parts/internal-parts/gearbox-parts/motor-connector-plugs-set-of-10-asg

Get or Buy some Deans Connectors: see eBay

If you want to reuse your current motor then here for the brushes: http://airsoftzone.co.uk/parts/internal-parts/gearbox-parts/replacement-aeg-motor-brush-set-nuprol

Though personally I use this motor as I find it give a higher rate of fire and its fairly reliable, not had one fail on me yet: http://airsoftzone.co.uk/m120-high-speed-long-type-motor-gnp?filter_name=m120

Open the gearbox (loads of videos on Youtube on how to do this) and basically rewire the gun using nothing more than a soldering iron, some solder and time. You might want to have a heat gun and some shrink wrap to prevent shorts and make it super tidy, this way you can ensure there are no shorts.

Also whilst you have the gearbox open you may as well shim the gears http://airsoftzone.co.uk/parts/internal-parts/gearbox-parts/shim-set-10x-0-10mm-10x-0-20mm-asg, regrease them, ensure the AOE and air seal is good, personally I would also install ceramic bearings http://airsoftzone.co.uk/8mm-ceramic-ball-bearing-set-6pcs-modify?filter_name=modify&page=2 this would make your gearbox run smoother if all done well and give you a high ROF.

The only thing you will lose using a different MOSFET is the 3 round burst, but to be honest I don’t think you will miss it when you have a working gun instead, but if you insist on having it there here is where you can buy the ETU alone:

http://airsoftzone.co.uk/parts/internal-parts/gearbox-parts/etu-electronic-trigger-unit-burst-mosfet-for-cm16-series-v2-gearboxes-gng

 

[Shizbazki]

Haha i find it funny that whilst typing this recommending Sitting Duck to answer and lo and behold he answers

 

[chirpy456]

Thanks guys for responding! I don't know much about aegs. I'm thinking about like what SittingDuck said, to just rip it out and change my whole wiring system. What are some good parts I could get to get the decent trigger response the etu had. It was good at the time, until it crapped the bed. What parts are similar to the etu but much more reliable? Keep in mind I don't have much money to spend on this. Thanks again, I hope to wait for a response!

 

[Shizbazki]

Basically the stuff I linked you to is pretty much the best out there.

 

[Sitting Duck]

Haha i find it funny that whilst typing this recommending Sitting Duck to answer and lo and behold he answers

Click to shrink...

11/10 though on that shopping list

To the OP - the main problem is where do you start & where do you stop ?

I still think you should speak to retailer - gotta be under some warranty or at least ask

I think OP might be over the pond - US if you refer to Walmart, we say Asda over here

If you are Stateside then either Brill Armoury or Clandestine will be two great places to source bits

However, you could sort out the short and likely the ETU mosfet in tube could be replaced - this might be covered under some warranty

You could go absolute nutz and look at a BTC Spectre in there but that is $100 unit + fitting

I mean a switch, (you will need a spring for switch and G&G use a bigger v2 switch spring like a v3 switch spring I found), mosfet, new selector plate will still add up getting onto maybe 1/3 to 1/2 of the Spectre is what I mean

plus it depends on your skill level and your budget

I'd certainly look at chatting to retailer first, a Predator is not a cheap as chips gun to learn teching on & sure you would like it up n running nicely

I mean yes - you could open her up, change the bits that need changing

or

you could go absolutely nutz in there but that goes back to my "where do you start & where do you stop"

If you ask 6 people what they would do, I can say you will get at least 4 answers of just how far or what steps they would take it to

My FFR A2 has only the original cylinder head left in it I think as I went way way way overboard on it (yeah maybe not worth all that effort but hey ho)

If I was you, I'd try and contact retailer and see if they can sort it for you mostly under warranty

then if you wish you can grab another box to mess about with and learn on without ballsing stuff up

then either build up a spare old school gearbox or when your gun needs a service then you will have confidence/experience to overhaul/upgrade it

or just swap out the worn G&G ETU box for an old school mofo 13:1 bad a$$ responsive gearbox you built up in stages

up to you but that is the route I'd consider imho