So I crashed my P4 into a footy goal post a while back.  Bent one of the arms but nothing some selotape didn't put right till I got replacement casings.  Now I swapped them last night and this morning and upon power up I have come to my worst fears .... something isn't right ...   

To start I don't hear the beeps from the P4 which I knew wasn't a good sign, but after boot I get the error msg on the screen 'ESC Status Error.  Turn off aircraft and restart.  Contact DJI support if this continues'

I watched a few YouTube videos (as you do!) and am a Technician by trade so wasn't phazed by the job ahead of me but obviously I haven't put something back right or whatever...

HELP NEEDED PLEASE !!!!!!

You probably just missed something simple. Id just start over, make sure the connections are all good and ribbons are fully seated.

From what I remember you can check you esc status in the dji app. The Phantom 4 has 2 ESC board one left and one right, it's very possible you pulled a cable when opening the body. So check which ESC is causing an issue 1 for left & 2 for right.  I would also advise to redo it and just check you ESC boards. I hope this will help and you are able to fix the problem.

Ok thanks.  I'm just about to pull apart again now so fingers crossed I see a ribbon not plugged in properly or something...

Wish me luck! ...

Damn! ... pulled apart and couldn't see anything lose so disconnected any plugs and reinserted and put all back together, to have exactly the same ...

When I go into the DJI app for ESC  it shows as 'abnormal' and when I click on it it shows...

No.1 ESC-ESC Error. Contact DJI Support if it occurs again

No.2 ESC-ESC Error. Contact DJI Support if it occurs again

No.3 ESC-ESC Error. Contact DJI Support if it occurs again

No.4 ESC-ESC Error. Contact DJI Support if it occurs again

I think it's gonna take a better man than me to fix this which is a pity as apart from the crash I've had zero problems with this bird.  Love it and get immense pleasure from flying it but now looks like I won't be flying it again...

GUTTED!!

Somewhere I was reading that cutting and splicing the motor wires caused the IMU errors rather than unsoldering them from the board.  Something to do with a slight change in the resistance affects the IMU sensing.  Did you splice them, or unsolder and resolder them back?

Another had a post about the need to change all four motors as the leads were attached to get rid of the error.

Good luck!

fansa84fe8a4 Posted at 2017-7-13 05:19
Somewhere I was reading that cutting and splicing the motor wires caused the IMU errors rather than unsoldering them from the board.  Something to do with a slight change in the resistance affects the IMU sensing.  Did you splice them, or unsolder and resolder them back?

Another had a post about the need to change all four motors as the leads were attached to get rid of the error.

I did cut them, and even had to join a piece of wire to one cable and used a diff gauge of cable.  I wonder if this is the issue.  I'll go change the cable I think, and have another good look at connections while I'm there.  All I can do as not getting much help here really ...

Joining wire will cause errors so if all connectors are good I'd look there first. Hopefully you marked the motors and put them on the correct arms. Not sure if dji assistant or go log view will show more info for you.

calls4u2 Posted at 2017-7-13 15:52
Joining wire will cause errors so if all connectors are good I'd look there first. Hopefully you marked the motors and put them on the correct arms. Not sure if dji assistant or go log view will show more info for you.

I've swapped the piece of wire for the exact same gauge wire now and yes motors were swapped one for one from original casing to new so 100% correct.  The YouTube clip I watched they cut and shut the wires and had no problems but yeah with hindsight maybe should've un-soldered and re-soldered but thought the cut/shut method was going to be OK.  

I'm just Googling price of new motors and looking like I can get for $30 each so #120 odd to replace all, but just don't wanna pay out more for something that might not work, but I guess aint gonna find out unless I try!  Catch 22 ...

Funk this is frustrating!! .... and I don't think I have the patience to deal with this right now as got a lot of personal crap goin on in my life now.  Anyone got a rough idea of what this is worth as is? Do I sell as is or break up and sell ?!?!  

Any advice most appreciated!

I did a complete replacement on my shell recently. I unsoldered and resoldered all connections and it performed like new. If all plug connectors are good, I can't see it. Ring anything but your mother connections.

user042fabfec9 Posted at 2017-7-13 17:40
I did a complete replacement on my shell recently. I unsoldered and resoldered all connections and it performed like new. If all plug connectors are good, I can't see it. Ring anything but your mother connections.

Ok thanks.  I spose I have to weigh up cost of new motors now, hmmm!

Pauldw100 Posted at 2017-7-13 19:36
Ok thanks.  I spose I have to weigh up cost of new motors now, hmmm!

I can get for roughly $30ea AU delivered, can anyone beat this price?

Cheers

As a technician myself I get where you're coming from at the idea of ordering parts even though there may be a secondary or tertiary fault (we had this this week and it took a whole workday to find all the faults).
Get the multimeter out and test every point you can to make sure connectors haven't come undone from the board, if you took photos as you dismantled it, refer to them to be sure everything plugged in where it should be (if not, find some pics of dismantling drone online).
Good luck, I'm hoping your next post is to say 'IT'S WORKING!'

Pauldw100 Posted at 2017-7-13 21:14
I can get for roughly $30ea AU delivered, can anyone beat this price?

Cheers

I had the problem replacing a motor and splicing it. I had an ESC error on a phantom 3 advanced that had been working fine. I won't go into the whole story again, but when I replaced the suspect motor I still had the error. I took an ohm-meter and checked the new motor and it was fine, but when I check the connections at the motherboard it was open. I found a break in one of the wires about an inch from the board where the wire was broken under the insulation. I recommend also taking a new motor and using the leads already provided. They come already tinned up and everything. I was suspicious too from reading before I tried the repairs about damaging the board, it wasn't a problem and much easier for me anyway to remove the wires from the main board. Have you iron hot and ready and you won't have any problem. The quicker you can make your connection the better you will be. You don't want to stay on that solder joint for more than a few seconds. I'm sure if you kept heat on it for extended period of time you could do some damage to the board.
I don't know what the correct reading is you should get with your meter, but I found that you will have some resistance between any two combinations of all three wires. Anything that doesn't ring out and appears to be "open" is suspect. The broken wire caused me a lot of grief, but kind of glad I experienced it so I know what to look for now. Those power wires are actually 2-small wires inside of the casing. At least mine were that way. If you bird flew ok before, I don't see how it wouldn't be ok now. Check you wires and connections again. The ESC's  are looking for a signal from the motors, and if any wire is not making a good connection, it could throw out the error. Good luck bud!

Edit: As far as testing the motors I haven't found a way. You would have to have another main board setup. But I would check the motors first before just buying all new ones. That is exactly what I did and found out I wouldn't have had too. I am not sorry about having all new motors, but you get where I am coming from. For me, I bought all four new motors for $72.

RicardoGray Posted at 2017-7-14 11:20
I had the problem replacing a motor and splicing it. I had an ESC error on a phantom 3 advanced that had been working fine. I won't go into the whole story again, but when I replaced the suspect motor I still had the error. I took an ohm-meter and checked the new motor and it was fine, but when I check the connections at the motherboard it was open. I found a break in one of the wires about an inch from the board where the wire was broken under the insulation. I recommend also taking a new motor and using the leads already provided. They come already tinned up and everything. I was suspicious too from reading before I tried the repairs about damaging the board, it wasn't a problem and much easier for me anyway to remove the wires from the main board. Have you iron hot and ready and you won't have any problem. The quicker you can make your connection the better you will be. You don't want to stay on that solder joint for more than a few seconds. I'm sure if you kept heat on it for extended period of time you could do some damage to the board.
I don't know what the correct reading is you should get with your meter, but I found that you will have some resistance between any two combinations of all three wires. Anything that doesn't ring out and appears to be "open" is suspect. The broken wire caused me a lot of grief, but kind of glad I experienced it so I know what to look for now. Those power wires are actually 2-small wires inside of the casing. At least mine were that way. If you bird flew ok before, I don't see how it wouldn't be ok now. Check you wires and connections again. The ESC's  are looking for a signal from the motors, and if any wire is not making a good connection, it could throw out the error. Good luck bud!

Thanks for the input guys, but one thing mentioned above scares the hell out of me.  The bit about leaving  the soldering iron on for too long.  I don't think my iron was hot enough and I held it on one of the solders for well over a few seconds.  I really don't want to guess but we could be talking 10+ seconds, so I have to presume the worst and that I could very well have burnt the board out ...   

Fixing the bird has gone on the back burner for now as I have relies staying over, but next week I'll get all the motors off and see what the go is with the meter.

ALL help is much appreciated, and I'll update as soon as I know what the go is! ...

You certainly are a braver man than I am!  Hope you will solve your problems

Pauldw100 Posted at 2017-7-14 19:14
Thanks for the input guys, but one thing mentioned above scares the hell out of me.  The bit about leaving  the soldering iron on for too long.  I don't think my iron was hot enough and I held it on one of the solders for well over a few seconds.  I really don't want to guess but we could be talking 10+ seconds, so I have to presume the worst and that I could very well have burnt the board out ...   

Fixing the bird has gone on the back burner for now as I have relies staying over, but next week I'll get all the motors off and see what the go is with the meter.

Hey, I wasn't trying to scare you out of it! Just offering some advice. Hang in there and give it a shot.

Pauldw100 Posted at 2017-7-14 19:14
Thanks for the input guys, but one thing mentioned above scares the hell out of me.  The bit about leaving  the soldering iron on for too long.  I don't think my iron was hot enough and I held it on one of the solders for well over a few seconds.  I really don't want to guess but we could be talking 10+ seconds, so I have to presume the worst and that I could very well have burnt the board out ...   

Fixing the bird has gone on the back burner for now as I have relies staying over, but next week I'll get all the motors off and see what the go is with the meter.

I would not be too concerned, most people do not have a soldering iron that is powerful enough to properly solder those motor wires. What wattage is your iron?

Geebax Posted at 2017-7-15 15:13
I would not be too concerned, most people do not have a soldering iron that is powerful enough to properly solder those motor wires. What wattage is your iron?

25W on the sticker which to me doesn't sound too powerful, but I dunno..

Pauldw100 Posted at 2017-7-16 22:55
25W on the sticker which to me doesn't sound too powerful, but I dunno..

That is relatively low, I use a temperature contolled iron of 80 Watt capacity. It would get the job done pretty quickly. But even so, you have to really cook the joint to damage the board.

Geebax Posted at 2017-7-16 22:57
That is relatively low, I use a temperature contolled iron of 80 Watt capacity. It would get the job done pretty quickly. But even so, you have to really cook the joint to damage the board.

Ok sounds good.  I'll get the rest of the week out of the way as got relies over and will pull off all motors and check resistance on all and see what I get from that.  Will update as soon as I know.  Thanks for the input!

Pauldw100 Posted at 2017-7-17 03:13
Ok sounds good.  I'll get the rest of the week out of the way as got relies over and will pull off all motors and check resistance on all and see what I get from that.  Will update as soon as I know.  Thanks for the input!

Took a motor off and checked with meter across the wires.  No expert with a meter and basically couldn't get any reading across any combination of the 3 wires, not even continuity so yeah beyond my skills now and am over pulling it apart and putting it back so gonna throw it in eBay as is and good riddance!  .... too much of a head funk for me right now, but thanks for the advice anyway ...

I had a Crash and replaced full covers. I cut ESC wires and re-soldered. The ESC wires are two strands and each strand is lacquer insulated wire. You have to scrape or otherwise clean the wires before soldering or you will have resistive or no connections when you are done. Did you clean the wires?

fansad6ed80e Posted at 2017-7-19 11:17
I had a Crash and replaced full covers. I cut ESC wires and re-soldered. The ESC wires are two strands and each strand is lacquer insulated wire. You have to scrape or otherwise clean the wires before soldering or you will have resistive or no connections when you are done. Did you clean the wires?

No I didn't clean them.  I just wrapped each wire around itself tight and then insulated..

Pauldw100 Posted at 2017-7-19 16:34
No I didn't clean them.  I just wrapped each wire around itself tight and then insulated..

Then there is your problem. The copper wires are insulated with varnish. You have to use a sharp blade and scrape the varnish off all the way around the wire, then twist them together and finally solder them.

Geebax Posted at 2017-7-19 16:42
Then there is your problem. The copper wires are insulated with varnish. You have to use a sharp blade and scrape the varnish off all the way around the wire, then twist them together and finally solder them.

Ok am gonna get on it now.  Thanks! ...

Oh and before I forget to add. When I power the bird up and before the fan kicks in I can hear a (faint but fast) pip pip pip noise. Haven't a clue what or why, but *might* ring a bell with someone !?

Pauldw100 Posted at 2017-7-19 19:03
Oh and before I forget to add. When I power the bird up and before the fan kicks in I can hear a (faint but fast) pip pip pip noise. Haven't a clue what or why, but *might* ring a bell with someone !?

Ok would love to say I've spent hours and hours scraping all wires, rejoining, and soldering to have the bird fire up properly and work, but exactly the same as before.  Powers up, I hear this pip pip pip type of noise then the fan kicks in and I don't even bother using controller as till I hear to 'normal' set of tones when it boots there's no point.  Kinda disheartened by it all really as I has an awesome toy and now something that might go on the top of the Xmas tree when the time comes...lol

OK Pauldw100 maybe you just need to step back and have a rethink.
So P4 flew after your crash with a bit of sello holding it together? If yes then gives you a starting point and tends to suggest that repairs may be the issue BUT in the process of cutting, dicing, scraping, having a tinny or three, watching TV etc., you could have buggered something else. So if your electrical wires checked out OK (as per calls4u2 suggestion to get the multimeter out and test every point) then look at something else that has hit the fan. Must be a few guys around your way who could point you in right direction.
By the way did you replace the motors or not?
Could be worth a call to a couple of the local suppliers to see if they have any tech types on staff (google DJI Suppliers Sydney or try http://www.dji.com/where-to-buy )
If all else fails buy another one and keep tinkering with the u/s model. Hey and look on the bright side. With the weather the way it is you can't fly anyway.

sky wombat Posted at 2017-7-19 22:46
OK Pauldw100 maybe you just need to step back and have a rethink.
So P4 flew after your crash with a bit of sello holding it together? If yes then gives you a starting point and tends to suggest that repairs may be the issue BUT in the process of cutting, dicing, scraping, having a tinny or three, watching TV etc., you could have buggered something else. So if your electrical wires checked out OK (as per calls4u2 suggestion to get the multimeter out and test every point) then look at something else that has hit the fan. Must be a few guys around your way who could point you in right direction.
By the way did you replace the motors or not?

It flew like a bird before and after the crash.  It just cracked one of the arms top and bottom casing so I had to change them to sell it as was the original plan.  I've scratched all wires bare for good connection and twisted connections well and soldered.  I've had to extend 2 wires so maybe the extra join would cause problems, I haven't a clue tbh!  

As to checking with the multi-meter I used 2 diff and couldn't get a reading of any sort across any combination of the 3 wires and any setting on the meter, but generally in the Ohms settings as V isn't gonna be any use! ... but yeah, couldn't get a reading and don't know what I should be setting meter to and what to look for!

You really need a hotter iron for starters.

1. the solder points on the ESCs are quite large,
2. you're soldering two strands at once to each point,
3. the wires are solid core field windings wound straight around the stator. The 'motors' on each arm aren't really a full motor, they NEED the ESCs to generate pulses to the windings to get the rotor spinning.

All this adds up to make one GIANT copper heatsink sapping the life out of that poor iron. The ESCs can take a lot of abuse, you've probably not damaged them yet but at the end of the day, it's not great for their life expectancy. 50-70W is more like it, better to have to rush with a hotter iron then slowly heat up the entire ESC board waiting for something to melt, then risking a cold joint anyway.

At $30 each, you're waaaaay better off ordering new motors and just soldering them straight in. There are 12 joining tasks to do if you try and cut & shut the old wires, 24 if it turns out they're not long enough and you have to add wire. Any one of those fails and you heavily impair, if not lose a motor altogether, potentially dropping the expensive aircraft out of the sky. New motors come with the field wires pre-tinned and ready to solder straight in.

After all that you can rule out the motors. Check all other ribbon cables running around the bird, often they can have tiny cuts in them from hitting sharp edges that can escape first notice. Ensure there's no corrosion or other contamination on the gold contact surfaces. Avoid touching said contact surfaces with your fingers, use tweezers to handle the ribbon cables if you have them.

Dunno what the pipipipipip noise is but I've heard it on my birds. Kinda sounds like a very faint version of one of those diaphragm aquarium air pumps?

For reference, this is what a broken ribbon looks like, very easy to miss:

Also not all the dirt and fingerprints on it from handling it a few times. Not at all good to get that stuff on the contacts....

Goof Posted at 2017-7-20 04:55
You really need a hotter iron for starters.

1. the solder points on the ESCs are quite large,

I agree with you Goof. I offered some comments on the soldering issues earlier in this post. I found out the hard way too, better off buying the new motors that are already tinned up and soldering right into the main board. I am pretty good with electronics and have dealt with this type of stuff for years, but that coating they put on those wires is really tough! I tried scrapping, sandpaper, etc., and I just couldn't get good results trying to tin up the wires. I have a pretty hot iron, but after reading a few articles, most of the time you have to melt the coating off with a melting pot of some sort. No doubt that just twisting the wires together would not work for him. And yes, maybe there is a problem that he hasn't addressed yet from the initial accident. My understanding is that these motors are multi-phase type motors, and those ESC's are kind of sensitive. I'm thinking if they don't get a proper signals back they will not power up.

The ESCs have 'B' 'G' and 'W' written on them for the three wire colours so one cannot mix them up.  There are no sensors in the motor hubs, so the only thing the ESC can 'see' is the current flow out to each dipole.

I'm not sure what it takes to actually tin those wires, I'm sure someone with a bit of brazing know-how might have more of an idea. Melting pot + proper resin would be a good start, rosin cored 60/40 isn't going to cut it....

I appreciate the advice and replies ...

I stripped each cable back a good 10mm and scrapped off all the shiny crap from each wire, they were def bask to just the bare cable and twisted together well, then soldered.  I'd be shocked if the joins were not good enough but I dunno tbh.  

Anyone have any idea of what setting on the meter I should be using and even result from the meter across any of the 3 wires??  I don't even get continuity which surely isn't right ..

So yeah if anyone can give me an idea of what setting on a multi-meter and what I should be looking for across the 3 wires for a motor that would be great ...

Geebax Posted at 2017-7-15 15:13
I would not be too concerned, most people do not have a soldering iron that is powerful enough to properly solder those motor wires. What wattage is your iron?

Soldering is becoming a lost art! We've been taught (in the last generation) that when something electronic breaks, you throw it away and get a replacement. That even seems to be true for my home theater receiver.

And virtually no one talks any more about cold solder joints! Egads!

Art - N4PJ
Leesburg, FL

Art - N4PJ Posted at 2017-7-23 03:26
Soldering is becoming a lost art! We've been taught (in the last generation) that when something electronic breaks, you throw it away and get a replacement. That even seems to be true for my home theater receiver.

And virtually no one talks any more about cold solder joints! Egads!

I agree with that.  30+ years as a military trained electronics tech, it never occurred to me that I would become a dinosaur in my field.  No one does repairs anymore, just replace.  That being said, to the op, in all my years, I can say with confidence that about 90 percent of problems I encountered were bad ( cold ) solder connections.  The other 10 percent were mostly bad caps.  I would guess the solder connections also, based especially on your description of using a 25 watt iron.

Kneepuck Posted at 2017-7-23 10:00
I agree with that.  30+ years as a military trained electronics tech, it never occurred to me that I would become a dinosaur in my field.  No one does repairs anymore, just replace.  That being said, to the op, in all my years, I can say with confidence that about 90 percent of problems I encountered were bad ( cold ) solder connections.  The other 10 percent were mostly bad caps.  I would guess the solder connections also, based especially on your description of using a 25 watt iron.

When I was a boy, I had a neighbor who was an electronic genius. He said over and over again how he despised cold solder joints. In all the years since then, I must confess that I would have to look very carefully at someone else's soldering to identify a cold solder joint. But I certainly did learn how to watch the solder "flow" instead of just dripping  melted solder on a connection.

Watched a video several years ago of how a guy designed a wave-soldering system for chips and boards. Incredible where chips and other technology have gone.

Unfortunately, there is more and more support for trashing instead of repair. Watched a guy replace a huge motherboard recently. I asked him about repair. He smiled and said "...that motherboard costs around $100. The labor to replace the board is $50. If I trouble-shoot the board and it takes me 4 hours to find and fix the problem, it'll cost you three times as much!"

Art - N4PJ
Leesburg, FL

Pauldw100 Posted at 2017-7-23 01:39
So yeah if anyone can give me an idea of what setting on a multi-meter and what I should be looking for across the 3 wires for a motor that would be great ...

To conclude, I sold it in eBay for $530AU 'as is'.  Thanks for all the advice tho! ...