Matek F405 Troubleshoot | Multimeter Continuity Testing

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I plugged in my Matek F405 FC to my Matek FCHUB VTX and the whole thing powered down. I'll walk you through the whole troubleshoot.
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THANKS TO MATEK AND PIROFLIPRC for providing the FC and vTX for this review!
Purchase the Matek F405 flight controller here:
* Banggood - goo.gl/7QBx79
* GetFPV - goo.gl/jvYDJS
* PiroflipRC - pirofliprc.com/Matek-F405-FC_p...
Purchase the FCHUB vTX here:
* Banggood - goo.gl/oa5U8K
* GetFPV (does not appear to carry it--sorry)
* PiroflipRC - pirofliprc.com/FCHUB-VTX-W58G-...
Links above are affiliate links, and I will receive compensation if you use them.

[@ACROBORG]

I think these troubleshooting videos you're making are a hugely valuable asset to the community. I've been an EE hobbyist for years and understand the methodology to track down trouble in my quads, but find that friends who lack that background can figure out what to solder to what (most of the time), but when components misbehave they can end up doing more harm than good trying to sort it out. I've been using an inexpensive(ish) benchtop power supply and it's absolutely invaluable for testing. With it, I can bench test my quads at 12.6v / 3amps, watch the current bounce around through the start-up motor tones, and immediately determine if there's an unexpected load or short. Same with any individual component that needs 3.3v, 5v, etc. A smoke stopper is perfect for testing after a wreck out in the field, but the benchtop power supply can be had for under $100 on Amazon and worth every penny, though I suspect you already have one. So why not use that instead?

[@JoshuaBardwell]

Smoke stopper is dead simple, portable, light. It works wherever the quad is, whether I'm at my bench, desk, or in the field.

[@pemtax557]

Some good basic troubleshooting 101 ... anyone seriously involved in this hobby should gain something from this incident. Good job Joshua ...

[@richardt1]

Very educational. I am new to all this. I bought the multimeter you recommended in your “continuity” video. It was the first time I’ve used one. I was making a smoke thingy and figured I’d better make sure I didn’t cross any wires. I believe that not knowing how to test components is a real weakness for those in this hobby. Please continue documenting your trouble shooting for we noobs.

[@echobeefpv8530]

This freakin rocks !!! Troubleshooting actually explained , in plain English. I do this all the time, but could never put the process into a video. This is a great teaching video for all sorts of troubleshooting . I am impressed.

[@ragugakifpv901]

There's continuity at 9:13! I was just as surprised as you! Thanks Josh.

[@rl2109]

Thanks for posting this exercise in logic... We sometimes focus on a discreet component that appears to be the culprit, and then hit a wall when that component tests true and the problem is still present...! Good find!

[@fiskiee_fpv]

Thank you for making me smarter everyday.

[@rage-g2385]

So informative the whole process. Just learning here! Thx!

[@sosquadcopter6634]

You are very good at what you do my friend. I would dare to say, the best. Keep it up.

[@flughund]

Ah, I loved this one. Learned a lot about the thinking while troubleshooting. Thx Joshua.

[@seacprogrammer8455]

Amazing how three - four years later the Matek F722-SE is STILL the BEST FC out there PERIOD !

[@supersentient]

I am planning to build using this combo, and I didn't really love the idea of using the ribbon, but I probably would have been lazy just to get the build over with and get in the sky. I am going to solder to the pads provided first go now. Thanks for the information, you could have potentially saved me the headache of having to probe around myself.

[@Dav2112]

Nice video Joshua, I’m away to start a build using this combo so this information is really useful for me, thanks man.

[@masterrc_student4259]

Excellent vid

[@JT-jy2sy]

I always check for continuity between vbat+ and vbat- after a build before powering on first time. It saved me in one occasion when I soldered one of esc + and - the wrong way. Working late into morning and mistake is a common hazard.

[@ashtonfpv4883]

I smoked my first lipo as you dropped this video lol. I have a short somewhere and learned the hard way. Thanks for the video helped me understand why this happened

[@Politicallyhomeless957]

Allot of great info on this vid. Thanks josh

[@sunsetpark_fpv]

14:40 "That's pretty cool....." No JB - what's pretty cool is that you traced and figured out the problem! Thank you, great troubleshooting vid! PS - I bought a twenty something dollar multimeter from Amazon, and it seemed ok, but for some reason putting it into continuity mode caused it to beep endlessly, and I didn't understand why. Bought the Innova that you use and immediately received great feedback on continuity testing.......was even able to check the continuity on an 8 pin JST connector which connected FC and ESC....it was very liberating to the troubleshooting process......thank you 😁

[@berniepoppe9742]

Great troubleshoot.

[@KGFlyer55]

Outstanding explanation 👍👍

[@outlawdareal]

I learned something today. Thank you for that ! :)

[@sirBumpyCase]

OH BOY! i was scared there! the 5v on my pbd was broken, and this video helped me realise that my leds were shorting it out. All is fine. thank you.

[@seacprogrammer8455]

LOVE these FC's [Matek F722-SE] not the F405 (10/21/2021) Ordered a handful a while back since they are becoming HARD AF to get. Awesome video basically on potential ramifications of not properly seating your ribbon cables. Thanks as usual Mr. Bardwell

[@madforit9661]

I am pleased you did decide to do this video. We all get problems from time to time and you would be correct in saying. Its easier to make a video that everything in it goes correctly

[@JoshuaBardwell]

No way! The videos where things go wrong are my favorite. We can learn the most from them.

[@scrapsz1079]

Really enjoyed your trouble shooting analysis, keep up the good work! Do you have a video about that smoke stopper, if so could you put a link in your video description.

[@vchan1501]

Comment after I watched till 14:52 : It is common that 2 adjacent pins can be shorted if there is little 'play' between the ribbon cables and its contact. If I was doing the trouble-shooting, I will look for which pins in the ribbon cables are actually transporting the 5V and trace that contunuity (i.e. without power on, just use the DMM) along the route from the FC to the hub vTx board point by point, and one can see where exactly the short happen. Anyway, this is a wonderful video to show people the steps one should take to trouble shoot. You mentioned very good point of using Smoke stopper to limit current in short situations as well as the good practice to troubleshoot by testing continuity rather than testing with lipo connected

[@1337flite]

I had similar problems with my second of these, I never worked it out and it is sitting on my bench in the random junk bucket. I'll mess with it a bit and find out if I can get it to work - I might have "free" FC. I really love these boards both the OSD and AIO. Pair them with BLHeli 32 ESCs run 8/8 or 16/8 and Bf3.2 and they fly smooth as silk.

[@rogertinder668]

So I just got done building the 405 and vtx hub in an Alien. I really liked the idea of the ribbon cable and your first video made it look pretty straight forward to install. But, it really just isnt that easy. Getting the ribbon cable onto the hub was easy, the layout is open, and the friction lock easy to get to. Getting the ribbon cable into the 405 slot straight is another matter completely. There is a chip right next to the friction lock that makes it almost impossible to get to to push both sides in evenly, and from experience now, if you dont get it perfectly straight, and I mean perfectly straight, it wont work properly. After spending hours trying to get the ribbon cable to work, I finally gave up and spent 10 minutes soldering wires. Works perfectly, still a clean set up. I'm really pleased with the vtx on the PCB, and I have zero complaints other than the ribbon cable. My experience - just solder from the get go.

[@JoshuaBardwell]

Not sure why you had so much trouble... Bad luck I suppose. Glad the board has direct-solder pads if you need them.

[@h2o-fpv623]

Good video

[@emanuilvalkov5824]

Very educational, thanks :)

[@zachfpv4493]

gday josh i have just finished a talon build with the xrotor hobbywing omnibus f4 sd and smatport telemetry and smart audio are not working.I am guessing i need to invert telemetry?would no tele affect smartaudio?any ideas would be appreciated.thanks mate

[@tswoshman0016]

Cool ! Awesome !

[@Deadzone2024]

My Matek done exactly the same. So I just directly soldered it. All good and still working fine. I done the same as you with the multimeter and got same results. Apart from that problem it’s a good bit of kit. PS got mine here in the UK 🇬🇧. So think there must be a bad batch out there. But don’t let that put you of getting it.

[@Jaybux87]

Ordered mine from the UK and had the same problem, except direct wire still had a short.

[@tehllama42]

That just tells me that the one party trick the Matek F405/HUB combo brings to the table is worthless... Why not just get the HUB/PDB/VTX unit and an Omnibus F4 for less money?

[@patrickcol]

Good video Joshua, as usual. Can't help feeling there was some Treckie stuff going on there though.

[@pcorneillat]

I have accidentally short circuit my board, i see a short circuit with continuity mod on 3.3v and ground, so maybe i can fix my board if i can replace a component ?

[@chrism9149]

I just built a 230mm quad.My first.I continuity test the + and - of the drone. It beeped once fast then stopped but I'm getting a reading of between 600-1500 on the screen. Does that mean theres a short?

[@danjensen9425]

Dude from the beginning you were the goto guy for building tips and how to , last time I sent you a message it was about the crossfire rx issue . Anyway I bought two Mateo boards a 405 and a 722std . The 405 flips on take off and the 722 has issues as well , so I said fuck it and bought a JB board and a kakute f4 V2 . Both easy builds . Now that I watched your video here I will revisit the other boards and see if I can’t figure out the problem with them . Thanks

[@JoshuaBardwell]

Flips on takeoff see below. If the quadcopter instantly flips over when you arm and raise the throttle with props on, it is almost 100% certain to be one of these things: 1. Clockwise prop installed on counter-clockwise spinning motor or vice versa. 2. Flight controller not facing forward. Go to the Setup tab in the configurator. Tilt the quadcopter on all axes (pitch, roll, yaw) with your hands. The 3D model in the configurator should move the same as you move it with your hand. If it does not, use the Board Alignment parameter in the Configuration tab to fix it. 3. Motors not wired correctly. TAKE OFF YOUR PROPS. Plug in a battery. Go to the Motors tab. Turn on the "props are off" slider in the lower-right. Raise the individual sliders (1, 2, 3, and 4) one at a time, just enough that the motor begins spinning. The motor positions (1, 2, 3, and 4) should match the graphic in the upper left. If they do not, then either move the signal wires so that they are correct or use resource reassignment to virtually "move" the motors. 4. Motor spinning wrong direction. Do the same as step 3 but compare the motor direction to the arrows on the graphic in the upper left. If a motor is spinning the wrong direction, either reverse it using BLHeli (or whatever ESC software you are using) or swap any two motor wires with each other, which will reverse the direction. Many times, people swear up and down they have checked all of these things, and then come back to say oops I missed one you were right. So if you think you have checked all of these things and your quad still FLIPS OUT, go back and check again. If your quad is insta-flipping on takeoff, it is almost always one of these things.

[@Robnoxious77]

good to know, i’m about to build a rig with those two exact components.

[@rustygolfer3475]

Love my Matek AIO

[@chiefshalot2986]

I just tried a build with matek f405 and the fchub. Seemed to be work fine at one point but then I cant figure out why motors won't spin now or osd and camera dont work thru the fc. So I unhooked replace with xt60 and sp3 and it flys

[@maniac_fpv]

I made custom 6s1p and when its fully charged and connected to quad I hear only two first beeps in loop... but when its almost discharged and connected to quad its working... any solutions?

[@scotty562]

Thank you for this video. I was going to just plug the ribbon in when I got mine and fire it up. I will test for a short to ground now before doing so. This is actually good advice to test for before powering up anything. Anyway if the ribbon cable was simply misaligned were you able to fix it by moving it around so all of the pins line up correctly? This entire issue screams poor design.

[@michelrinaldi5458]

Hi Joshua. With this fc I found a problem relates to Blackbox. Sometimes when I am doing a slow loop with Blackbox enable the kwad became crazy and lost orientation. With Blackbox disabled nothing happens. Did you know this behavior?

[@JasperTielen]

Very nice, I assume you contacted Matek about it? You can get a replacement from the vendor, Matek is very generous with warranty.

[@aventhu1]

You can check the pins on the FC end of the ribbon cable while plugged into the PDB and powered up. It' tedious and I've used very small clothing pins with care to check ribbon cables. This would help positively confirm the failure.

[@rebelquadronfpv1065]

Live long and prosper.

[@mrmega328]

Yep most regulators have over current and over temperature protection, though sometimes those features don't always work :P

[@MBJFPV]

Please do a rf powertest on the matek vtx 😁🇩🇰

[@Meisterjogi]

Hey from Germany, I git the F405-OSD with the FCHUB-6S from Matek. After Installing the Blue LED ist blinking. What does this mean.

[@Gator-Forever]

That was a good one because I hooked up a new stack today and had same problem and this video saved my ass!I'm broke right now Josh but I'll get ua some money soon buddy.😊

[@st200ol]

That smoke stopper is a good idea to use on the bench, especially when you have what looks like a blob of sodder on the mat. :-)

[@JoshuaBardwell]

Yeah exactly. Or if you accidentally touch something with a probe that you shouldn't. Current limited power supply is also nice.

[@orangutanfpv271]

Hi Joshua, You are the only builder that I have have watched on youtube using a smoke stopper. Please could you give an idiots explanation to what one is, how its made and what it does. I did my last build without one but sounds like I shouldn't have. Thanks for your videos, i do always learn something new.

[@tchthsky]

search 'smoke stopper'

[@AndelosPhotography]

Joseph Rapson as the bulb is in series on the earth if there was a vbat short the bulb would take up the load and light up hence stopping it smoking the board, esc ect

[@higherground07]

what up josh. thank you for your continued guidance. i am running a matek f722 on the fchub vtx. all was fine, and all the sudden when i plug in vtx and esc's power, but i dont get the final chime, and i have one dim red light on the flight controller. if i plug into usb, with battery still connected, lights come up on fc, and i get the full cycle power up with chymes. tried bypassing ribbon cable, same thing. then i watched this video and am stumped

[@MrStevegibb]

I guess its possible the connector isn't aligned correctly on the pcb when they soldered it. An idea would be when installing this setup would be to check continuity between the ribbons edge conductor and the first pin on the connector to make sure the alignment is correct before putting the other end in the flight controller.

[@JoshuaBardwell]

That's a good check.

[@chiefshalot2986]

I will try it cause at one point I do remember my motors spinning in bf

[@FibroFantastic]

I learned something today

[@CarbonGlassMan]

That's a great idea to check everything as you go. I did that today and everything was fine until the last thing. Installing the receiver. But the receiver wasn't bad. The solder connections weren't bad. That's just when the 3.3v regulator decided to blow up for no reason. After talking to people I discover at least 1 guy has had four 3.3v regulators go bad on Mamba F405 FCs. And that's what I have. A Mamba F405 mk3. The regulator gets blistering hot after 2 or 3 seconds. I'm so pissed. This hobby man. It's the most frustrating thing I've ever done. We have nice weather planned for this weekend and I was really ready to fly my first HD build. But nope! Not happening. The regulators won't be here until Monday. Then I can find out if it's just the regulator or did it also blow the processor.

[@Plan-C]

at 12 minutes in I am screaming "it must be the ribbon cable" lol

[@vanl6674]

Is there any wrong with your multimeter? Why its still displayed a voltage when you are not touching anything? Thanks for great tips!!!

[@importryderify]

You r amazing

[@joshzimmerman3750]

Have you done anything with the Betaflight F4 board?

[@jeffbabb5]

i actually had a similar issue with an Omnibus F3 board the other day. vbat and ground were shorted when the FC was soldered up.

[@petertothRC-FPV]

Good show Joshua.I damaged the Strix JB Signature 4s parallel charging board while plugging in the battery balance plug.Good thing for fuse but now i see a trace showing on the opposite side of the board.

[@JoshuaBardwell]

Yeah it's probably dead. You have to be super careful plugging them in. People have asked about making a version with polyfuses. It would add some cost but would protect against that.

[@petertothRC-FPV]

When i say showing i mean the coating is gone from heat it melted and exposed the trace.It works fine though the board is very crowded and the balance ports are hard to be precisely plugged in.If i had tiny fingers it would not be a problem.I will need to replace that fuse and cover the trace with nail polish.Good show brother.

[@VilleF1N]

I was wondering why it has taken so long for part 2 of the Matek install. Got a little worried since i am getting either the vTx PDB or the regular, depending on if GetFPV get's their shit together and adds the vTx version to their store, before i finalize my order.

[@flipcrash8537]

If it was a poorly aligned ribbon cable would it correct itself by wiggling the ribbon or reinstalling it? What's the chance that it is the alignment of the ribbon connector to the board from the manufacturer causing the power and ground to be misaligned that is the problem?

[@JoshuaBardwell]

Yes that's a likely cause. It's pretty hard to misalign the ribbon cable although anything is possible.

[@R-K61]

I have this setup and its worked fine for a couple of months but after a tumble the 5v and grd are now connected, if I disconnect the ribbon from the fchub the aio pdb still has continuity so its the pdb but where is the short?

[@JoshuaBardwell]

Something is broken in the PDB. Possibly internally. The answer is to desolder things one at a time until either the PDB is naked (in which case it's toast) or you find the thing causing the short.

[@thomashaley3830]

If you check the continuity of multiple ground pads and they are linked why do you suggest groundi g the vtx and camera in the exact same spot?

[@JoshuaBardwell]

Because of reactance. kzbin.info/www/bejne/anLLfpd9msR4mK8

[@Brunmed]

Hi, Assuming that the manufacturer doesn't cover that board on their warranty and there's definitely that same situation. Is the current on those pins to high to eliminate that pin that is shorting the current, being that a ground pin or a positive pin? Please bear in mind that it's a defective board that you cannot return for some reason. Apologies for my English. Cheers, Bruno.

[@brandonwoodford579]

Hey Joshua. Did you notice the ribbon cable being slightly off, once you found out?

[@mooculleniphone]

If you doubt your powers you give power to your doubts (nice Mystery Men you put in there).

[@JoshuaBardwell]

I love that movie.

[@pizzatuner4176]

About measurement, if you check a 5V/12V line put an appropiate load parallel. Maybe a LED (virtual sign too) or an resistor. For example to check a 12 Volt 1A source put a 10 Watt LED parallel. Mayba a little Board with a 3way switch 5v/500mA;12V/500mA;12V/1A load is a good tool. Btw your smokestopper is a bit to heavy with "Ampere" protect this little conducting paths on RC parts like FC/PCB boards. Think about a power supply unit where you can adjust/limited the current for your application. Its much saver and costs nowerday not much. There are good old vintage powersupplies arround 30 Bucks that have this possibility. Regards from germany Stefan

[@JoshuaBardwell]

+pizza tuner the smoke stopper here is mostly to protect me from blowing up the battery.

[@pizzatuner4176]

Really no need to. I "blitz" some old screwdriver accus to blow out the anodes (often some cells of older NiCd accu change polarity) with my Lipos. And this short ~ 50A didnt hurt them. Believe me anything on your rc stuff vaporized before the Lipo gets touch on his limits. The only way it make sense to protect is an sensilblier "Smokestopper" or simply a good old (or new) power supply with adjustable continiuty. Maybe a good stuff for your next videos. Like your content, always a thumbs up for you. Happy to fly, Regards from Germany Stefan PS: Write me a mail and i give you some summaries.

[@lokisdream8438]

Hey JB. Can I make an important addition to the possible issues when installing this FC? I just received this F405 OSD the other day and immediately updraded all drivers and then the firmware to 3.2.2 with no issue. second I loaded my Starter presets to betaflight as well as followed you video to set m5 as softserial for FrSKY telem. Finally I completed install an failed to check continuity and plugged lipo. The board lit up but quickly lost power . I also lost power at micro USB. Upon first visual inspection I noticed a very ,"very" small solder bridge at the ribbon connection leads on the back edge of the ribbon connection plug that sits very close to cam and vtx solder pins. I then realized that when soldering these pins I dabbed the solder tip against the ribbon bridge slightly and that is my issue. I was in a rush and now I am paying for it. At this point I am thinking that I must have blown a voltage reg on the F405 and I will need to replace. Can you give me any suggestions in relation to the F405 voltage regs and/or other possible factors? I have Falcon's (RIP) vlogs on replacing these v/regs and I am comfortable with micro soldering. "Even though my soldering is why I find myself in this position." Thank you...

[@JoshuaBardwell]

There is an intentional solder bridge between two adjacent 5v pins on the ribbon connector. I'm not sure what exactly is wrong with your board though...

[@51im]

Is the ribbon cable bidirectional or is there a FC end and pdb end. You might find that the ribbon cable has the contacts slightly off to one side at one end but off to the other side if turned round.

[@JoshuaBardwell]

It's bidirectional I think. But hey maybe I'm wrong about that.

[@johnbednarz1424]

Wish I saw this yesterday, lol. I had a brand new flight controller that would not power up. On the 9 volt pin, I had 9 volts, but on the 5 volt pin, I had 0 volts. I checked the cable for continuity and it checked out fine. I went back and forth with the manufacturer, they said there QC is very good and everything is tested. I suspect it might be a 5volt regulator, but, I never checked for continuity from 5 volt to ground. It would have gave me a little more info. Anyway, they are replacing it, but it took a whole week of sending them pictures and videos.

[@DP69264]

I know this is an old video but I just got the same board with the fchub vtx to go with it. First few flights everything was fine but now all of a sudden my osd just reads 0v. Have you ever had this issue? I'm going to reflash the board and hopefully that helps but was just wondering if you've had that happen with the matek f405.

[@JoshuaBardwell]

I haven't had that, no. Check the Power and Battery tab to see if the voltage source has changed. It should be "internal ADC".

[@DP69264]

I did check that after i posted my question and it was set to "none". After I changed it to "internal ADC" I still got 0v on my osd and in betaflight itself. I power cycled and still no joy. After some frustration I came back powered up the quad again and all of a sudden it was back. Not sure what the deal was but it seems to be working now. This is BF 3.4 and i know from some of your videos it has been finicky so maybe this is something else to keep an eye out for. Like i said in the original post I had not adjusted this and it had worked fine for the first few flights on this board. Thank you for the help i will let you know if it comes back again.

[@hideovt6263]

Agree that continuity test is mandatory on every build on every power rail prior before plugin lipo to power everything.

[@ivanvodopivec8022]

Good for you! You found the cause. What about some BNF FC that has nothing labled and multimeter is beeping at every contact i make? 😂😂 i talk about cheapest Cetus FPV kit brushed drone.

[@elevatedfilm]

What do you think about working ESD safe? in mobile phone repair it's a big thing.

[@JoshuaBardwell]

I ought to, but I don't. So far it hasn't been an issue.

[@vchan1501]

Question at 9:21 : At this point, swap your +ve and -ve probe to test G and +5V again to see there is a beep or not, or better off, don't use the beep to confirm the short, use the actual ohmmeter

[@bluedeath996]

Hopefully Matek has separated the power lines so the 5V and Ground lines are on opposite sides of the ribbon now. That would almost entirely eliminate the issue especially if they put a not connected line next to one or the other (or both).

[@ryan3859]

Be interested to see how this works for you. I wanted this to be my go to stack but am second guessing it. The vtx is the most disappointing. It worked o.k. to begin with but is no longer outputting the same power it originally did with roughly 1 months use. Also, one of the vtx push buttons has failed. The F.C. when you first plug in a battery at the start of a session always says no gyro, and won't arm. If you replug the battery everything will be fine. The voltmeter is also inconsistent. You can plug in a freshly charged battery and the buzzer will beep at you and say low voltage time to land. Re-plug the battery, and it will read correctly. I also have only a sample size of one, so take it for what you will.

[@ryan3859]

I also have 2 Omnibus F4 Pro v3's. One is running 3.1.7 and the other is running 3.2.1. Both are stable with none of the issues I have with the matek. I can't remember which firmware the matek is running at the moment. The problems are annoyances at best, the rig still flies awesome.

[@xiandan54]

Hey Joshua, my brand new fc went to shit today after crash, upon plug in there’s light but not finish boot up, and no response via usb, now that the mcu and 3.3v regulator are both hot, is it worth my time to try change that 3.3v linear regulator? Or is my mcu pretty much dead dead?

[@JoshuaBardwell]

I mean it sounds like you have nothing to lose by trying to change the regulator but I think the mcu is actually what fried.

[@xiandan54]

@@JoshuaBardwell I do have to buy the hot air gun and regulators hahahha, brand new fc, hit the grass ground rolled, r38 prop exploded and that was it, ground is hard though, 20 degree day. Wha you think? Current spike? Will it help fc’s longevity if I power my vtx/cam off a separate bec?

[@HuntAndFishExchange]

I wired up an AIO esc, flight controller and pdb board. Plugged it in with a smoke stopper, all soldering is good, but I only get the first half of the tone when I plug it in. I assume this means the board is bad???

[@JoshuaBardwell]

This means the ESCs are not recognizing throttle signal from the FC. The board is probably fine.

[@HuntAndFishExchange]

Joshua Bardwell - ok thanks

[@HuntAndFishExchange]

Now I got to figure out why I am not getting power to my receiver

[@Rip1Outdoors]

I have the same problem now with the Xilo quad bundle I'm building. I am going to win though!

[@charlescole5434]

You mentioned that reversing battery power can burn up a trace on the board. I reversed power leads from an esc to the fc (kakute), got smoke. Put new esc and different motor but I get nothing from that motor. Inspected the board and no popped capacitors or visable damage... Is it likely that I burnt a trace?

[@JoshuaBardwell]

Reversing the power will destroy electric components. I was talking about a short. If you reverse-bias an ESC, it is dead forever.

[@charlescole5434]

Yes the esc very much destroyed itself, however I am wondering whether the FC will be salvagable. I have swapped the esc and motor (with one's I know work) but when I arm, that one motor does not function.

[@Umsterdam]

Joshua Bardwell You mean reverse polarity? Love your videos,keep them coming.

[@MaxBeamer]

I had this exact problem but with a 4in1 esc to a fc via pins

[@hippychip1159]

So.. let me get this right, so you had a duff hub/hubs? or when you plugged the ribbon in the steams got crossed and the made a good hub duff? thinking about this for my next build with the halo frame from bludz so would be good to know if its better just to throw out the ribbon to start with? and just solder the job up direct...?

[@R-K61]

Just ordered the same quad with the same matek setup and after my neato just died with the same problem I'm thinking I may change boards.

[@hippychip1159]

Richard Harwood how'd it die? After a bad slam? Ribbon cable moved and cooked the FC?

[@R-K61]

Not a bad slam, just hit a branch and it wouldn't arm or show life afterwards, when I dismantled it all seemed buttoned up well but on testing it had continuity everywhere even to the sd card housing.

[@hippychip1159]

Richard Harwood harsh, and is that it? It's had a short run through the hole system? You unplugged the vtx hub from the FC and it's still showing continuity everywhere?

[@R-K61]

Everywhere but as to what shorted first I have know idea, I'm a bit confused as to hardwiring stopping the problem unless the ribbon instigates the short.

[@akshaykumar-th9ps]

I ordered this FC and HUB, after watching this video little fear to buy or cancel. Please guide Joshua Bardwell

[@JoshuaBardwell]

+akshay verma I'm still happy with mine.

[@29jvskate]

so im wondering sir, what if we just not use the ribbon cable and soldered the fc to the pdb since it seems to be caused from the pinout of the ribbon cable holders. in other words would soldering the fc to the hub traditionally? would this fix this issue?

[@JoshuaBardwell]

Yes, that's what I did.

[@29jvskate]

your aweseom!! these videos are really good help. happy to hear all is well :)

[@diy-dash6103]

My Omnibus F7 Board came with a wiring harness that had the pinouts the opposite way around. Luckily I noticed before powering it up. "Always check your wires, then check them again". Also, ribbon cables are made for Raspberry Pi's not quads. Don't know why manufacturers both using them for fpv.

[@romanekster]

Hi Joshua, great video as always! I'm wondering if you could help me trouble shoot a problem? I accidentally soldered my xt60 cable the wrong way around on the pdb and the polarity was inverted and boom magic smoke. So I changed my pdb, fc, vtx, camera, xt60 and cable. Everything is working fine except for my fpv. When I hover for a few seconds the video feed gets all snowy and then snows up the whole picture. The pdb I'm using is the matek 5v/12v simple pdb. My vtx is connected to VCC at 12v on the rail labelled VCC vtx. The unify pro hv powers the OSD and camera from it's own 5v supply. My kiss is connected to VBAT with the main xt60 lead. Should I rather power the kiss fc from VCC aswell. I have VCC 12v/5v camera rail still available on the PDB. What could cause my vtx to snow up so badly? Is it perhaps the esc' s that could be faulty? I was able to flash my escs and fc no problem. Or it is it the noise from the fc because it's connected to VBAT straight? Please help I've really tried all the forums with no luck :(

[@JoshuaBardwell]

Video feed getting snowy says to me that the vTX is shutting down. Usually this means the vTX is overheating but you said it happens when you hover, and this is backwards from overheating. Overheating is usually fixed by spinning the props to move some air. If video goes out when you spin the motors, normally that's electrical noise. But that would manifest as black lines in the video, not snow. So I'm a little bit mystified... I guess I would change out the vTX and antenna next.

[@romanekster]

Thanks for the quick reply, really appreciate it! I'm going to change the aerial and vTX next. I will let you know if works. Thanks again

[@romanekster]

Hi Joshua, what do you think of this vTX Matek Video Transmitter 5.8G VTX-HV w/ BFCMS Control? Thinking of getting this instead of the tbs unify..

[@fabiopignata]

Hi thanks for the vid :-) since a few weeks I am struggling with an issue after crashing a Tyro129 and I am having trouble with RX connection with the quad. I tried both an R9MX and XM+, they both used to work with this quad and still bind ok with the remote. Quad behaves ok when connected to betaflight, all features work, vtx is ok, gps locks ok. I even updated the firmware, no issues. Only thing that won't work is RX-FC connection, I checked wirings severeral times, pins continuity is ok, I also bypassed the plastic connector and soldered the RX straight to the FC (also trying different input uart pins), none worked. FC led blinks red all the time, 5V pins are ok, 3v pins are ok, ground is ok, no overheat whatstoever. R9MX seems to connect intermittantly (remote keeps saying "weak signal", "signal lost", "signal ok") Any ideas on how to throubleshoot this? How can I be sure that the eachine GPS F4 FC is fried? I run out of ideas... thanks for you help 🙂

[@ChrisQuadFPV]

Did you ever find the problem

[@fabiopignata]

@@ChrisQuadFPV nope :-(

[@ueigerchaves5726]

Josh, my Vin / Vout from my fc is not workin, the continuity test can unravel this mystery? I have no images at all with the pads, but the cam signal directly to vtx signalis perfect... but no osd that is bad.. (Kakute v1.4 fc)

[@JoshuaBardwell]

Confirm that you have wired correctly: cam to Vin, vTX to vOut. If the OSD chip on the FC has died then you will have the symptom you are saying. Confirm that you have NTSC/PAL set correctly in the OSD tab.

[@ueigerchaves5726]

Joshua Bardwell i get a multimeter today, i will try the continuity to see.

[@ueigerchaves5726]

Joshua Bardwell i forgot..thanks!

[@joshkaminski7112]

Hi JB love your videos there very helpful too me and I'm sure many others but I have a question that I have yet to find an answer too. Built a quad for a friend and once I had it finished plugged it into cleanflight and when you spin up either motor 2 or motor 4 they both would spin I checked and checked my solder connections and even moved motor 2 and 4 signal wires to pads 5 and 8 on the FC to try and fix it still the motors always spin together can you please give me some guidance to try and fix this.

[@JoshuaBardwell]

Two possibilities. One is you are using Dshot and the two motors are sharing the same DMA channel. If that's the case, you have to use resource reassignment to get the motor outputs on a unique DMA channel. Or just switch to multishot and never think of it again :-) Other possibility is that you bridged the motor outputs with solder but since you moved the motor outputs that's unlikely.

[@joshkaminski7112]

Thanks for your very fast reply! I tried running multishot on it and even removed the signal wire for motor 2 and they are still both spinning. I'm assuming at this point the 4in1 esc is shorted somewhere inside and I will have to get a new one. Thanks so much for your help.

[@SigmaOfMyParts]

In the video yoh can see some pins of the connector are soldered together. How about checking them and fixing it there? Normally the cables are fine and you can not connect them wrong easily.

[@JoshuaBardwell]

The bridged pins are intentional. That is the 5v line, which shares two wires. It is the same on both of my boards. It's not an error.

[@RectifiedMetals]

It took almost the end before I started suspecting the ribbon alignment. That connector is flawed. I've seen it too many times in other tapes of equipment. You have to get that alignment exactly correct.

[@JoshuaBardwell]

I mean, in theory, you shouldn't be able to misalign it.

[@mrlazda]

You can't misaligned ribbon cable, they always have connectors at end (ribbon cable is what you use for PATA HDD or floppy disk in old PC computers) which always align with pins in socket. But this is not ribbon cable cable, this is flat flex cable and they are easy to misaligned if you do not connect them properly and they are generally pain in ass.

[@RectifiedMetals]

You're both right. However I've had so manny problems with surround sound receivers give issues. The connector and cables have too many inconsistencies. I've had too many mis matches, it's to the point it's the first thing I try with these receivers. Many different brands.

[@smokeyzx14]

greeting Joshua, I'm new to the Quad hobby, I just built my first quad, and I have the omnibus f4 pro FC stack with the I think Mateksy PDB that connects with the ribbon cable, the problem I'm having is that, everything works as long as I got the USB cable hooked to Betaflight , but as soon as I disconnect I don't get power to FC from PDB, rechecked every wire that was soldered, everything in right place but after I unplug, receiver don't light up and has no signal with transmitter??????

[@JoshuaBardwell]

Power from USB but no power from LiPo usually means the 5v regulator on the FC has died. You can power the FC from an external 5v regulator or you can replace the FC.

[@smokeyzx14]

Joshua how do I go by powering the FC from an external power source, would like to try this before I buy a new FC

[@R-K61]

as an update I completely removed the ribbon connector on the pdb and still there's a + to- connection.

[@R-K61]

Well i couldnt let it lie so i removed all the connected wires one by one testing all the time then with my dermel i removed the ribbon support area , the esc corners the battery connections and all of those tiny tiny capacitors? and still had continuity, finally i removed one of those square grey blocks with 100 on them, it was the one closest to the K on the mateksys logo and behold no continuity........ think i deserve a new board and a glass of wine.

[@Roby0593]

nice wallpaper XD

[@DennisOostdijk]

How can I re-enable USB vcp in BetaFlight? that I accidentally have disabled in BetaFlight, on my Eachine Minicube Flytower F3.

[@JoshuaBardwell]

+Dennis Oostdijk re flash the board with full chip erase selected. Rebuild your configuration.

[@DennisOostdijk]

I've tried, but get this message: Failed to open serial port. (all my drivers are being updated in windows 7)

[@northernflyer5311]

Mine is a power to gnd short on the FC board, somewhere.