View Full Version : Help CP+ tail motor problem

05-08-2009, 08:05 AM
I recently aquired a cp+ heli used, and pretty much out of the box the tail motor burned up without any crashes or strikes of any kind. I replaced the motor and got it all wired in, but now when I plug in the battery(transmitter is on and set to zero inputs) the tail motor goes full blast. I checked the voltage running to it and it is at a constant 12v...full bore. I'm wondering is there some problem in the 3in1 unit or possibly the transmitter or receiver not getting signal or what?

05-10-2009, 11:46 PM
That's a sign you blew your 3in1 when mosfets fry the blow in the ON position

If your good with electronics I have complete directions on the fix here http://www.wattflyer.com/forums/showthread.php?t=37290&highlight=blew

05-11-2009, 06:51 AM
Try servo reversing and make sure you've got the right polarity. Also, checking your gain and proportional rudder trim on your 3 in 1 might help. Vortex is probably right but theres always a chance.

Hope this helps,

05-11-2009, 08:30 AM
I believe I have an extra chip of the stock configuration if you want to try your hand at soldering I could sent it to you given a standard postal address. Alternatively I have all the part numbers listed in my post, you can try digikey or newark or any one of your favorite component sellers to obtain it.

I understand hearing your 3in1 is gone is a pain but the good news is if you opt to fix it yourself the part cost is only $2 / mosfet (2 main motor and 1 for the tail).

I'd highly recommend fixing it yourself as I'm still running mine without a problem for over a year. If you have any questions about the repair feel free to PM or post here.

05-13-2009, 04:41 AM
Thanks for all the input! I ordered a few mosfets off of digikey and tried my hand at soldering for the first time today. Total Success!!! After 3 hours of painstaking learning on that stupid soldering iron...Came out with a flying heli...which i promptly changed. I learned my lesson...fly in zero wind...at least until i get better. I've got everything fixed up and flying again...thanks all!

05-13-2009, 06:04 AM
The good news is that now that you know how to fix your mosfets you don't even have to get fuses like everyone else recommends. In reality the part is actually cheaper if you bought them in bulk. I bought 9 because i figured I'd screw them up but I didn't so now I still have 6 spares.

I didn't actually buy stock parts either my new part allows the motor to burn out instead of the ESC which is a lot better when it does the dead chicken dance.