Blinking red lights and RTH

[gunslinger]

Had a weird day with the P2V today. I won't even mention this morning's problems.

I took it out for a second time today, late this afternoon. I set everything up exactly the way I always do. I saw home lock kick in and then the nice slowly flashing green. I had a lock on nine satellites. Life is good. I took her up to about twelve feet,and she was holding a nice tight hover. I looked down at the screen for a second and when I looked up I saw quickly flashing red lights. I started to take her down, and tried to stop it at around six feet, when I realized I had no control. It very slowly continued down, gently touched down and shut off...

The speaker in my Nexus isn't that loud, and the P2V was only about ten feet away from me and twelve feet up so it would have drowned out any Klaxon sounds coming out of the Nexus. This was obviously an RTH, though I have absolutely no idea why. I shut it down, pulled the battery and slammed the battery back in. I didn't let it get far from me, but I ran out the entire battery without another problem. Any idea WTF that was all about? I'm baffled... :shock: :shock: :shock:

-slinger

 

[gunslinger]

I still don't know what could have triggered the RTH and I'm very concerned that it didn't go up 60 feet before it auto landed... It's possible I may have turned my body a bit trying to read the screen in bright sunlight and the P2V and the TX lost connection. If so... why did it come straight down from around twelve feet?


Has this ever happened to anyone else?

Thanks...
-slinger

 

[OI Photography]

Sounds more like it triggered an autoland due to low batt reading, instead of RTH. Don't ask my why it thought it was that low at the time, but that would explain why it didn't follow full RTH protocol.

 

[gunslinger]

Sounds more like it triggered an autoland due to low batt reading, instead of RTH. Don't ask my why it thought it was that low at the time, but that would explain why it didn't follow full RTH protocol.

I've been researching this all afternoon, off and on, and that's exactly what I came up with. I have the original rounded spring loaded battery contacts. I'm wondering if I'm starting to see that problem... This thing has been pretty damned bullet proof up until now. I really don't want to be afraid to fly it. I'm going to contact DJI to see if I can get anywhere with them.

Thanks a lot for the response. Much appreciated...

-slinger

 

[OI Photography]

No problem! It was just a guess based on what you saw...and yes with the history of the P2 batt connections, that's definitely where I'd start if I were you.

Best of luck man!

 

[RCRookie]

Could it have been switcholgy ?.. accidental S1 RTH activation maybe ?

Just a guess.

Maybe there is a replacement for the data pin to the newer style
I clean all my contacts with deoxIT almost every time.

 

[gunslinger]

I actually spoke with DJI tech support a few minutes ago. I was caller number twenty-nine when I first connected. I was at my desk most of the afternoon, so I just listened to their hold MUZAK for a few hours.

The guy I spoke with was knowledgeable, easy to understand and pleasant. He immediately diagnosed it as a battery connection issue. He asked what version of the firmware I was on, etc... He also agreed that the "old style" spring loaded pins are a problem and fairly certainly a problem in my case.

They will gladly fix this for me if I don't mind being without the P2V for a month or so. Or... I could purchase the new part and self install.

This tells me that they DO have good support, just not enough feet on the ground. Much too long phone wait time and MUCH too long repair time...

-slinger

 

[flyNfrank]

I was given a similar option yesterday when discussing warranty. I said to send me the part and I would do the work myself. Now had I lived across the street I would have let them take care of it.

 

[jeffrg270]

Hi there,

I was wondering, when you look at the connection pins, do either of them look bent at all? And does the spring on them still work ok?

Maybe one thing you could try first is cleaning the pins with alcohol, and also cleaning the contacts on the battery with an alcohol swab too.

It might make the connection reliable and solve your problem.

Thanks,
Jeff.

 

[johnbowen]

I've had similar issues the last few times I've flown. First noticed on full power up or forward it will blink red on he battery power, but immediately return to blue upon lesser power. It seems to do this, even when the battery is far from 30%. Today it it started blinking red lights on the p2V, yet the battery was above 30%. This too was intermittent. Finally it decided to attempt to auto land, despite the battery level not being in the critical level (below 15%). Fortunately I had returned home and was hovering above my yard, 60 feet up. I decided to drain the battery completely by holding on to the skids and applying full up on the throttles. It ran a good bit, despite at "0%" battery.

I checked my contact pins, both are straight, move in/out fine. Battery contacts was a bit dirty, corroded but not excessively so.

Msuspect it might be one of the three battery cells is discharging too quickly and the software indicates low battery based on that low power, low capacity cell, causing on the red LED hull lights and/or attempts to, auto lands when any of the cells drops below 30/15%. I'm certain the app reports the average level for all three cells. You could have one defective cell the other two fine and it could cause such a problem. My hypothesis at this point.

 

[gunslinger]

Hi there,

I was wondering, when you look at the connection pins, do either of them look bent at all? And does the spring on them still work ok?

Maybe one thing you could try first is cleaning the pins with alcohol, and also cleaning the contacts on the battery with an alcohol swab too.

It might make the connection reliable and solve your problem.

Thanks,
Jeff.

Both pins are straight and appear to have the same spring tension they always have. I DID notice that there was a little discoloration on the pads on the battery side that the pins make contact with. I cleaned them off and cleaned off the pins and four flights later... no problem. (fingers+toes crossed)

-slinger

 

[mustang_52]

I had this issue also but only after i had added fpv equipment to it. My best guess is that instead of the battery reaching the 2nd warning level and auto landing itself , the battery voltage drops too low and takes over. I was not using my monitor to verify that and I had sent mine back for the newer model but it's what I thinks happening. Are you guys running fpv stuff on yur phantoms?

Sent from my HTC One using Tapatalk

 

[gunslinger]

I had this issue also but only after i had added fpv equipment to it. My best guess is that instead of the battery reaching the 2nd warning level and auto landing itself , the battery voltage drops too low and takes over. I was not using my monitor to verify that and I had sent mine back for the newer model but it's what I thinks happening. Are you guys running fpv stuff on yur phantoms?

Sent from my HTC One using Tapatalk

Mine's stock except for a FlyTrex...

-slinger

 

[npalen]

I wonder if the Phantom does NOT do the ascent to 60 feet when it is within a very short distance from home. Perhaps the firmware calls for an immediate landing in that case?

 

[jimre]

I wonder if the Phantom does NOT do the ascent to 60 feet when it is within a very short distance from home. Perhaps the firmware calls for an immediate landing in that case?

Auto-land (critically low battery) is different from RTH (lost control signal). It definitely does *not* ascend when Auto-land is triggered - it starts landing itself immediately right where it is. You have to shove the throttle all the way up to fight the descent, and have some control over the landing. But at this point, it *is* going to land.

I've had this happen prematurely with one battery, but not the other. I've cleaned the contacts on that battery, and am waiting to test it to see if that fixes it.