Drowned P2 - Now lights blink and turns itself off?

[mysticalice]

Hi
Haven't flown the phantom 2 in probably 3 or 4 months, so I took it out this afternoon, and within 1 minute I crash it in the pool. Fished it out immediately, so was only in the water for about 5 seconds, but upside down during that time.

Took everything apart and thoroughly dried it, with canned air, a hairdryer, etc.

This is what it looks like now (see attached image)

Plugged a battery to it, and did the powerup (pressed the battery button twice).

The lights all blink RED - > YELLOW - > GREEN - > RED, then I hear a click and it turns itself off. The whole process takes ~2 seconds.

I uploaded a video to youtube of me doing a power cycle:
http://youtu.be/iZc2bKN9Cek

Hopefully it's not completely fried... it's only got maybe an hour and a half of flighttime since getting it, with a gopro, 2 axis gimbal, 600mw video transmitter, etc.

Right now I'm just trying to get it to power up - gimbal is attached but gopro is not, neither is video transmitter

Any help would be appreciated

 

[RDCF550]

You have a short on the battery line, most likely one of your ESCs is shot, but you'll have to do some testing to tell. See if the click is coming from just one of the motors, and then start by desoldering that ESC and try powering it up again. If it still doesn't power up, desolder another one until you find the bad one. If you get all 4 removed and it's still not turning on, then your main board or battery is shot.

Just drying it out isn't enough when you get water damage, it should have been taken completely apart and rinsed with a lot of 90% or better rubbing alcohol to absorb the water that was in there in all of the little nooks and crannies, the motors and especially the battery too as it's just a sponge since there's no way for the water to get out as easily as it can get in.

 

[mysticalice]

I guess I could just desolder the ground on each ESC, one at a time, right? (instead of desoldering both leads).

Would it (potentially) power up with all ESCs removed? How would you tell it's powered up at all with no lights or sounds (with all 4 ESCs disconnected)?

Battery is not the problem, as I've been using my two additional batteries (haven't tried with the battery that got wet)

I ensured prior to starting it up that it was thoroughly dried - new battery, motors rotated by hand and several minutes of compressed air through each one. I am certain whatever damage was done was done while it was underwater, not since drying it (and attempting to start)

 

[mysticalice]

The 'click' is coming from just one of the motors. Next I will desolder that one motor and give it a try again. Going to be Monday a.m. before I am back in my office with access to my equipment before I can try that.

In the meantime i'll overnight another ESC. Is it as simple as (desoldering one, soldering the other?, unplugging the one, plugging in the other) - is there anywhere that sells both the motor and ESC?

 

[RDCF550]

Yes you can desolder just the ground, but also make sure the 4 wire cable is unplugged as there is a ground connection there as well.

If there are no ESCs connected and the battery stays on, then the short is gone.

Water damage doesn't take place under water, not quickly anyway, it does that much faster when the water starts evaporating, ie letting it sit after drying it off. Compressed air is also every bit as good at blowing water into even more places as well as blowing it off of things, but at least you didn't rice-a-roni it up.

Correct, 2 wires to desolder then resolder for the new one and then the 4 wire cable. If you can do SMT rework, the FETs are usually all that go bad on the ESC board.

http://www.rcgroups.com/forums/showthread.php?t=2264946

 

[mysticalice]

Just an update on this.
I replaced the ESC and motor that were making a clicking noise on startup. After I tried it again another motor started doing the same thing. I disconnected this motor and the Phantom did its regular startup lights and sounds. Yay! So I have another ESC and motor on the way. These were the two motors that were completely submerged so it makes sense they are both bad.
one thing I noticed when it did its startup (with the second motor disconnected ) was the gimbal started thrashing around, vibrating. So I may need another gimbal. Also I tried starting the motors but they wouldn't start. Not sure if this is normal when the Phantom only detects 3 motors hooked up.

Will let everyone know when the other ESC and motor arrive and I've had a chance to solder them on.

 

[RDCF550]

The Phantom has no way to know how many ESCs or motors are connected. If everything else is good with it, even with no ESCs/Motors in there or all 4, it will still start up. If you had the top off and the GPS unplugged, then that's most likely why they wouldn't spool up, as it has to detect the GPS module or it's a no go, since FW 3 on up it's been that way.

 

[mysticalice]

You were right - plugged in the GPS module, and did the power up, and the 3 motors started right up. Good stuff!

Guess I just need the last ESC replaced and another gimbal (will post in classifieds) and I should be back in action!