Nazgul5 only 3 beeps after reassembly

[Stijn]

About a month ago I got a Nazgul5 and it flew great without any problems. However, I had to disassemble it to take with me on a flight and when reassembling it I made a dumb mistake and mounted the FC upside down which caused the micro USB port to slightly touch one of the solder joints between the motor and 4in1 ESC. When I plugged in the battery there was a bit of smoke and I quickly unplugged it again. Now when I plug in the battery there are only three beeps. When I connect FC to betaflight configurator lights blink on the FC and everything in the app seems normal.

I am very new to the hobby so don't really have the equipment to troubleshoot further. I hope I have given enough information for someone more experienced to see what the problem could be.

 

[bzmot]

Normally three beeps only would mean your FC is toast. But since it comes up in BF normally I would try reflashing it, it could help. Does it arm? Do your motors spin in Betaflight?

 

[Stijn]

Normally three beeps only would mean your FC is toast. But since it comes up in BF normally I would try reflashing it, it could help. Does it arm? Do your motors spin in Betaflight?

thanks for the reply.
I reflashed it but still only three beeps. The motors don't spin and the transmitter does not connect so I don't see how I could arm it. I did notice that in BF under power state it says that there is a 1 cell battery connected with a 3.7 voltage. Before traveling I did put the battery on storage charge which was 3.7v and have since charged it but maybe I did something wrong there...

 

[bzmot]

So it doesn’t bind? What RX is that?
Are you trying to spin the motors in beta flight with a LiPo plugged in? It won’t spin without the battery.

 

[Stijn]

So it doesn’t bind? What RX is that?
Are you trying to spin the motors in beta flight with a LiPo plugged in? It won’t spin without the battery.

I'm using the TBS crossfire nano. With the LiPo plugged the RX does not seem to have power and there is no light on it. In BF with the LiPo plugged in it sometimes says 0v and sometimes 3.7v. Moving the sliders in the motors tab has no effect on the quad.

 

[bzmot]

Then sadly I think the FC is smoked. Or at least the part of FC which supplies power to UARTS and also the voltage meter. I could be of course wrong but replacing the FC seems like a sensible option.

 

[bzmot]

but just to be sure I’d check if your rx works fine elsewhere, you might have fried the receiver too (hopefully not)

 

[mrmund]

Not a judgement, I'm just curious. Why did you have to disassemble it take it on an airline?
I've flown with DJI qwads in my carry on without a problem. Will there be an issue if I try to take an FPV

 

[Stijn]

Not a judgement, I'm just curious. Why did you have to disassemble it take it on an airline?
I've flown with DJI qwads in my carry on without a problem. Will there be an issue if I try to take an FPV

Flying to a country with some strange drone import rules. Easiest thing to do was to turn it into drone parts.

 

[mrmund]

Ah, got it.

 

[droneguy]

Your short likely burned up the voltage reg part fo your circuit that is required to power your UARTs. The three beeps means the ESCs are initializing, but they aren't able to communicate with the FC hence the missing additional beeps. Unless you are prepared to do some diagnostics, and re-soldering, you will need to replace the FC. Good news is that your ESCs are probably OK and iFlight sells the FC as a separate unit in addition to the selling as a stack so you can buy just the FC.

 

[Stijn]

Your short likely burned up the voltage reg part fo your circuit that is required to power your UARTs. The three beeps means the ESCs are initializing, but they aren't able to communicate with the FC hence the missing additional beeps. Unless you are prepared to do some diagnostics, and re-soldering, you will need to replace the FC. Good news is that your ESCs are probably OK and iFlight sells the FC as a separate unit in addition to the selling as a stack so you can buy just the FC.

So I replaced the FC but it still won't communicate with the ESCs. The bat light does go on on the new FC but the RX doesn't power up on battery power(it does on USB power). Could it be that the ESCs are faulty?

 

[droneguy]

The battery power goes through the 4in1 ESC board where there is also a BEC (voltage regulator) the regulated voltage then goes across the wiring harness that connects the ESC to the FC to power the flight controller. If you are getting power on USB and not on battery, you likely have a failed voltage regulator on the 4-in-1 ESC. You can easily test this with a multi-meter. Look at the pin-out for the wiring harness and check for 5V where it leaves the 4-in-1 ESC

 

[droneguy]

So I replaced the FC but it still won't communicate with the ESCs. The bat light does go on on the new FC but the RX doesn't power up on battery power(it does on USB power). Could it be that the ESCs are faulty?

You should also invest in a good smoke stopper before fiddling with wiring and soldering in new components. The viFLy Short Stopper 2 is probably the best on the market. It will save you lots of $$$ in mistakes.

 

[Tomk_]

I love the viFLy Short Stopper 2. It's almost worth the price for the on/off button when binding. So much easier to just push the button on the viFly than trying to plug the battery in while holding the bind button.

 

[Stijn]

The battery power goes through the 4in1 ESC board where there is also a BEC (voltage regulator) the regulated voltage then goes across the wiring harness that connects the ESC to the FC to power the flight controller. If you are getting power on USB and not on battery, you likely have a failed voltage regulator on the 4-in-1 ESC. You can easily test this with a multi-meter. Look at the pin-out for the wiring harness and check for 5V where it leaves the 4-in-1 ESC

I am getting 0V on the 5v pin on the wiring harness coming from the ESC and the lights on the FC are very dim while on battery power so it probably is the voltage regulator. Is there a way to replace this or do I have to get a new ESC?

Edit: I went over the information on my ESC and I'm pretty sure it doesn't have a BEC (Succex-E 45A 2-6s BLHELI_S Dshot600 4-in-1 ESC). Is there something else that could cause my FC to not get enough power?

Thanks for the advice on the smoke stopper. The viFly doesn't ship to where I live so I think I'll make my own.

 

[bzmot]

You honestly don't need that and they're not 100% reliable either (too sensitive sometimes). Just hook up your multimeter to the battery pigtail - red to red, black to black, settings to Ohm and if it shows anything above 3kOhm, you're golden, no shorts.

 

[droneguy]

You honestly don't need that and they're not 100% reliable either (too sensitive sometimes). Just hook up your multimeter to the battery pigtail - red to red, black to black, settings to Ohm and if it shows anything above 3kOhm, you're golden, no shorts.

The viFly v2 is quite good and better than anything else on the market. I wouldn't hesitate to recommend it to anyone especially newbies. It can be the difference between an expensive mistake and a second chance at resolving any problems before it cost you money.

 

[mrmund]

The viFly v2 is quite good and better than anything else on the market. I wouldn't hesitate to recommend it to anyone especially newbies. It can be the difference between an expensive mistake and a second chance at resolving any problems before it cost you money.

And the V2 has an on/off switch which makes binding so much easier...

 

[metheguy]

I am getting 0V on the 5v pin on the wiring harness coming from the ESC and the lights on the FC are very dim while on battery power so it probably is the voltage regulator. Is there a way to replace this or do I have to get a new ESC?

Edit: I went over the information on my ESC and I'm pretty sure it doesn't have a BEC (Succex-E 45A 2-6s BLHELI_S Dshot600 4-in-1 ESC). Is there something else that could cause my FC to not get enough power?

Thanks for the advice on the smoke stopper. The viFly doesn't ship to where I live so I think I'll make my own.

did you ever get an answer to this question? I'm having the same exact issue and i dont think the ESC you mentioned has a BEC (per the spec).