Jammed in fire mode

Hey, my CTW is jammed in fire mode.

When I switch from safe to semi, the CTW automaticly fire one shot without pulling the trigger.
The CTW will not fire more shots if I pull the trigger again.
When I switch to auto, the CTW starts fireing without pulling the trigger.

Trigger has normal movement when I pull the trigger. So nothing is obstructing.

I have check all the wireing. It seems to be all good. No scratcs or shortning.

The blue light works ok.

No dirt cover sensors.

Does anyone know what part that is broken. Is it the ECU?

I use Celcius 11.1V 2400mA battery.

Hmm sounds like the ecu. Could possibly be the mosfet as well. Its hard to figure which one though. Does it also do this if u leave the selctor in a mode and disconnect and reconnect batteries?

blindmank13 wrote:Hmm sounds like the ecu. Could possibly be the mosfet as well. Its hard to figure which one though. Does it also do this if u leave the selctor in a mode and disconnect and reconnect batteries?

I have disconnected and connected the battery several times. Always in safe thou.

If you do as I said with the upper open or gun split it can possibly reset the ecu. Mine does 3 round burst on both modes time to time and I do that and usually works. But as I said could be the mosfet. Its hard to tell unless you were able to test both if you had an xtra ecu or mosfet lying around. Does it ever go back to regular operation or is it now stuck like this?

blindmank13 wrote:If you do as I said with the upper open or gun split it can possibly reset the ecu. Mine does 3 round burst on both modes time to time and I do that and usually works. But as I said could be the mosfet. Its hard to tell unless you were able to test both if you had an xtra ecu or mosfet lying around. Does it ever go back to regular operation or is it now stuck like this?

It does not help to disconnect and reconnect battery as you describe.

it could be the trigger contact sensor, it sounds like it is made (pressed) all the time, thats why the trigger may not do anything, 'cause it's already pressed.
if you can, check this out, just to be sure; if its not that, the next in line is the ecu.

gycu wrote:it could be the trigger contact sensor, it sounds like it is made (pressed) all the time, thats why the trigger may not do anything, 'cause it's already pressed.
if you can, check this out, just to be sure; if its not that, the next in line is the ecu.

The trigger is mechanicly pushing a push putton on the ECU. This push button swich works just fine.
In fact I can change the Blue light from bright to weak and back. This proves the trigger and button on the ECU is ok. And also that the ECU might be ok.

I suspected the ECU at first, but I'm now suspecting the MOSFET unit. I open MOSFET and tried to figure it out. But it's not easy. It is 2 MOSFET pcs on the PCB. And it's 4 wire going between ECU and MOSFET. RED is power and BLACK is ground. And this is used to power the ECU. I guess the YELLOW and WHITE is for the ECU to control each MOSFET. I have not figured out if the two MOSFET are connected as power driver. Or just one for semi and one for auto.

I would like to know what voltage I'm supposed to measure at the YELLOW and WHITE when selctor switch is in safe, semi and auto.

oddi wrote:Hey, my CTW is jammed in fire mode.

When I switch from safe to semi, the CTW automaticly fire one shot without pulling the trigger.
The CTW will not fire more shots if I pull the trigger again.
When I switch to auto, the CTW starts fireing without pulling the trigger.

Trigger has normal movement when I pull the trigger. So nothing is obstructing.

I have check all the wireing. It seems to be all good. No scratcs or shortning.

The blue light works ok.

No dirt cover sensors.

Does anyone know what part that is broken. Is it the ECU?

I use Celcius 11.1V 2400mA battery.

Changed to new ECU and CTW is good as new.

Glad to hear it.

A bit offtopic, but I'll give it a try... If you still have the old malfunctioning ECU, and are willing to part with it in the interest of science and CTW internals knowledge-base, there's a couple of experiments I'm willing to try on it, but I wouldn't risk a fully functional piece. I'm not asking for a donation, I'm willing to compensate for something akin to 40% of its price, and postage fees as well.

A team mates CTW had this problem and it turned out to be the trigger board. Replaced it and the problems were gone.

These ECUs seem to be very temperamental. As we speak, I have three faulty units on my workbench. One does only semi, one opens the braking mosfet without closing the activation one, thus burning it, and the third is acting funny... led blinks on/off and you can hear a faint whine coming from the board when the led is off.
And the 3-bb-burst unit in my CTW sometimes fires only one or two shots in burst mode.

I'm keeping a brand-new spare available, and if there's "electrical issues" it's always the first swap I do to diagnoze.