Wiring the HobbyKing KK 2.1 Flight Controller

(To see a list of all my Quadcopter blogs, click here).

I spent the better part of my Saturday slowly and carefully figuring out how to wire everything up and then executing the wiring. It’s pretty easy, but I found no single source explaining everything.

My first questions were how do you provide power to the flight controller and to the radio receiver as no one seems to talk about it and there are no obvious power connections.

The flight controller gets its power through the positive/negative leads from the ESC connected to the M1 header. So you simply connect the motor and the flight controller has power.

The radio receiver will get power from the flight controller. I’ll show how this is wired up down below.

Here is how I wired up the KK 2.1 flight controller and the Fly Sky FS-R6B radio receiver.

  • Unplug the motors from the ESC if they aren’t already. The motors shouldn’t be fired up until initial testing is done.
  • Put some tape on each motor spindle so you will be able to tell which way it is spinning. The propellers should not yet be mounted.
  • This is my connection diagram:


  • Looking at the diagram, note each motor’s number. Oops, I see I numbered them wrong. Front left is 1, then go clockwise 2, 3, 4. I accidentally swapped 3 and 4 in the diagram.
  • The ESC controller for each corresponding motor is connected to the header pins M1 through M4 on the right hand side of the controller.
  • The black wire for each ESC plug goes on the right side of the connection, near the edge of the controller.
  • This website shows a really clean way to connect the radio receiver to the flight controller:


I’m going to borrow his picture in case it disappears because it clearly illustrates what to do:


Between my notes and his pics, hopefully this is clear. You only need to provide the +/- on channel 1. For channels 2-5, you simply need to connect the signal pins. I was originally going to wire the +/- to all 5 channels which would have added a lot of unnecessary wire. This solution is much nicer.

Here is my setup. Each wire is separately colored which might also help illustrate what is happening:


At this point I’m ready to plug it in. Note: I discovered that if you don’t have the radio on before you power up the quadcopter you will get the error No yaw control. Just make sure the radio is on first.

And it fired up on the first try! Yay!


This entry was posted in c-quadcopter, Quadcopter. Bookmark the permalink.

39 Responses to Wiring the HobbyKing KK 2.1 Flight Controller

  1. Alex Willis says:

    Dear Random Internet User,
    Thank you for publishing such an insightful method on how to correctly wire these components because I had absolutely no clue and I could find nothing on how to do it anywhere else online.
    Another Internet User

    • Johnik says:

      As alex above says,there is virtually no info for complete beginners with zero computer or electronics knowledge…thanks again Dan !

  2. willburt says:

    Is it ok to power the receiver from the KK controller? Is there a danger of brown outs? I’m a bit stuck on this problem atm.

    • Dan TheMan says:

      Yes. Note in my diagram that +/- is connected between M1 on the flight controller and channel 1 on the receiver. I don’t know how much power the flight controller can source but it has been enough for my receiver.

  3. nitin jaiswal says:

    my quad is not taking flight can u help

  4. Gurdeep says:

    I prepared my quadcopter but there is a huge problem that I can’t calibrate my kk2.1.5 board and transmitter is flysky ct6b.I want to learn how to arm it and complete calibration.So,if you can help me then plss help..

    • Dan TheMan says:

      I haven’t played with this stuff in a long time and you didn’t give any specifics about what you are having issues with. I would suggest going to my table of contents and looking at all of the Quadcopter entries to see if any will help your specific issue. If not, try google. It usually has the answer, you just have to look. I’ve not seen kk 2.1.5. If it is at all different than 2.1, you may need to be searching specifically for that revision.

  5. Krieg says:

    THANK YOU. Can’t understand why this info is not included with the kk controller, or the wires either. Great job my friend!

  6. Mike says:

    Great instructions – as indicated by an earlier comment there is really no info on how to wire up.
    One question. The controller specs indicate input voltage is 4.8-6.0 V. My power distribution board connector would be supplying 12V to the controller. Is there a built-in regulator on the board to bring the 12V supply to 5V?

  7. Rohit says:

    Does this flight controller support brushless motor ??????


    DEAR sir , i am using kk board 2.1 version and i am not able to arm the quad .. i tried calibrating the esc’s but they does not calibrate i get the beeps correct but still no motor movements please help sir .. i am usign a FS CT6B transmitter

    • Dan TheMan says:

      Are you moving the left joystick to the full down and left position? I believe that is the arming position while full down and right disarms.


        YES SIR i have tried that quite a lot the throttle is pulled all the way down then it gives some beeps and taking to the left doesnt seem to work all the channels are reading correct on the kk board and revised i have a kk board 2.1.5 sorry for the mistake

  9. Dan TheMan says:

    You have me stumped.

  10. Rohit singh Chauhan says:

    Hello sir thanx fr ypur help i got my motors working up almost together all thanx to u.. And now a little priblem is arriving .. My frst motor would not start up as fast as my rest three are.. What can be the glitch??

  11. niraj says:

    Kk2 is not working with fs i6 plese help this is my first drone

  12. Rohit Patil says:

    will kk2.1.5 and fs ct6b work out to be a good pair??

  13. Dan Zaikin says:

    I wired everything up (using Afro Esc’s) as explained above.
    When I plugged in the battery, the ESC’s give off a beep…
    …and then nothing.

    After that, they beep once every few seconds, yet the kk never powers up.

  14. Harsh says:

    hi I am not able to arm the kk 2.1.5 board . All the beeps are correct. Plesce help me.

  15. Prem says:

    Hi sir, I have been using kk 2.1 for my quadcopter (X). I have calibrated all the esc s’ perfectly (25A esc Unbranded ones bought from the local rc shop).but when i connect all the escs to the kkboard and power it on and armed it ,the motor 1 was not starting (no movement or rotation). It is starting when i give full throttle whereas remaining three motors were working perfectly.This 1st motor was giving the same problem even if re-calibrated each and every motor many times.I couldn’t find what the problem was! Could you please help me out ! Am using Turnigy Tx (9X9) & Rx. 1400kv motors. 2200mAh Battery 3s 25C 11.1V.

    • Dan TheMan says:

      I would suggest swapping motors and ESCs around to see if either the motor or the ESC has an issue. If not, then work back to the KK 2.1 and make sure it is connected properly.

  16. rumayel hassan says:

    hello sir,
    my when I connect my kk 2.1 to receiver, the receiver doesn’t get lights up. infact it does not get power. what should I do? please help me sir. I have wired it all correctly. but still no use. where can be the problem sir?
    thank you.

    • Dan TheMan says:

      Well, now. The rcvr gets power from the KK board. So you should have single + and – leads coming from KK into the rcvr. Is the KK powering up? If it is, then something is wrong with these leads (or maybe the rcvr itself). Look at my wiring diagram carefully as + and signal are on opposite sides.

      Good luck!

  17. everett johnson says:

    Hey so I was just wondering how your battery connected into all of this? thanks for the great insight on all of the other wiring!

  18. mani says:

    Hi hello

    My quadcopter is not working and kk2.1.5 show prfect but motor not working
    How can i start my quadcopter

  19. anil says:

    hi after “armed” my motors are spinning very less time(2sec to 5 seconds) after that nothing is working may i know what changes i need to change ..i am using fs-i6 transmitter and receiver with kk 2.1.x board .

  20. Dan TheMan says:

    It’s been so long since I did this project I really don’t recall much about it. However, from your symptoms it sounds like the battery, motors, and ESCs are good. There is something about the controller that causes a shutdown, so I’d focus on that.

  21. ALI HASSAN says:

    Hi I need your help please, I’m using kk2 flight controller I’m using simonk esc, i have connected all the three esc one by one to channel 1 but only one esc out of 3 power up the quad, is that how it’s or the remaining 3 are not good?

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

This site uses Akismet to reduce spam. Learn how your comment data is processed.