Solved ESC starts up but won't spin up motor on input signal

snoato

Junior Member
Hey folks,

I recently started reactivating a quad build that I had laying around for 2+ years (thought I mention that so that people don't get confused with the pretty outdated hardware) and didn't touch since. Back when I left it one of the ESCs was broken, so when I picked it up again I ordered the same model (it's a cheap 12A Afro ESC). A few days ago I got the replacement. The one I got had a substantially bigger form factor (I would say 1.5x the size) but from what I could tell it looked like most components where the same and since it had the same firmware and specs I thought I just give it a try.

I wired up everything, tested each part and the ESC starts up and does startup calibration just like all the others do and enters ready state. Problem is, this one ESC doesn't seem to respond to input signal from my flight controller (a Naze 32 rev 6, same as back then). While the others turn off their green LED and the motors start spinning, the new one just stays green and the motor doesn't move a bit.

I tried resoldering the wires, using a different motor (that I knew was working), different ports on my FC (thought maybe the dead ESC might have killed the port or something). To test it I used the Betaflight manual motor control menu in the Configurator app as well as firing the motors up with my Tx.

Every suggestion that might help me fix this is more than appreciated, I spent around 6 hours trying to find the culprit. I hope I included all the hardware information you might need.
Hope you guys can help me!

[Update: I tried calibrating the ESCs and the new one didn't react to that either, it's almost like it's deaf on it's signal pin]
 
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Merv

Site Moderator
Staff member
That’s a head scratcher, I was going to suggest recalibration, but you’ve done that. Any way to pull the ESC off and try it with a Rx. Could you have another dud?
 

snoato

Junior Member
That’s a head scratcher, I was going to suggest recalibration, but you’ve done that. Any way to pull the ESC off and try it with another Rx. Could you have another dud?
So I actually did a similar thing just now. I ordered two new ESCs (just to be sure), and I did a complete clean build outside of my quad to eliminate the influences of whatever I might have done there. Only thing that stayed the same is my FC. I don't think another Rx would change a lot because I did test it with both my Rx signal and the built in Motor control thing from Betaflight (where you can manually control all motors via the configurator). The result of this setup was the exact same of my original testing. I doubt that both ESCs have the exact same error coming from the factory so it must be something that I am doing that is wrong.
Thank you though!
 

snoato

Junior Member
What was the issue back then?

Did you calibrate your ESCs through the Naze? If so, do you have the power on the ESC connected to an ESC BEC or to a PDB or a lipo?
The issue back then was that the ESC was physically destroyed (magic smoke) due to a crash and a bad mount.

I calibrated the ESCs using Betaflight on the Naze (I used these steps: power to 100% with battery disconnected, connecting battery, waiting for the ESCs to finish beeping, turning down the power, disconnecting battery). While the 3 old ESCs on my quad did the calibration perfectly fine, the new one didn't do anything.

On my quad I have a PDB but when I did a separate testing build, I soldered an XT-60 to one of the new ones I got and hooked it up to the battery that way (was the fastest way to do the job). I don't use a BEC.
 

Merv

Site Moderator
Staff member
So I actually did a similar thing just now. I ordered two new ESCs (just to be sure), and I did a complete clean build outside of my quad to eliminate the influences of whatever I might have done there. Only thing that stayed the same is my FC. I don't think another Rx would change a lot because I did test it with both my Rx signal and the built in Motor control thing from Betaflight (where you can manually control all motors via the configurator). The result of this setup was the exact same of my original testing. I doubt that both ESCs have the exact same error coming from the factory so it must be something that I am doing that is wrong.
Thank you though!


Try a good ESC on that side of your FC. Could your FC have a fault?
 

snoato

Junior Member
Try a good ESC on that side of your FC. Could your FC have a fault?
I tried that with a good one, it worked just fine, as it did on my quad.

The FC *could* have a fault, but it would be a very weird fault to affect only the new ESCs on every port, while the old ones work fine on each of the ports. But I don't wanna eliminate the FC as the source of the fault just yet. Based on my testing I think it is unlikely though.
 

snoato

Junior Member
Can you calibrate it directly through the receiver? If not, (since you tried @Merv s suggestion) I think it's safe to say you have a bad ESC.
I'm not quite sure how to do that, but I'll try.
How likely is the chance that 2 completely new ESCs are bad, but show the normal behavior on startup? Unlucky me haha :/
 

cranialrectosis

Faster than a speeding face plant!
Mentor
Calibrate ESCs from the receiver like you would for a plane. Take the flight controller and betaflight completely out of the picture.

Of course, do this with the props removed.

It would be supremely unlikely that you get multiple bad, new ESCs. I would be far more suspicious of Betaflight or that Naze. Calibration and running from a receiver or not should definitively prove where the fault lies.
 

snoato

Junior Member
In Betaflight, what ESC/motor protocol are you running? Many older ESCs can only handle PWM.
I didnt get to check it out yet but I remembered that my Rx is a FrSky SXR, which means (as far as I know) I cant directly connect it. However what I could try is producing a PWM signal with a Raspberry Pi and hooking the ESC up to that.
 

PsyBorg

Wake up! Time to fly!
That or its that old blheli factory flash veraipn is NOT the same as a blheli flash from a new .hex thing with that gear being so old.

I would try reflashing and see what that gets.
 

snoato

Junior Member
That or its that old blheli factory flash veraipn is NOT the same as a blheli flash from a new .hex thing with that gear being so old.

I would try reflashing and see what that gets.
Yeah I just had the same idea that maybe an old firmware is on that doesnt understand Oneshot125 wheres my old ones might actually have a newer firmware (which would be weird but who knows). I have to try that!
 

snoato

Junior Member
YES I FOUND THE CULPRIT! Apparently the replacement ESCs I ordered don't "speak" ONESHOT125! I try to flash the firmware! Thanks so much to all of you that responded and tried to help me! :D