Hi there !Moving my battery set from P4Pro to P4PRo V2 I have problem with 2 of them.
I have 5 batteries, 3 high capacity (one old, one from an obsidian version, and one from the new P4P2) and 2 standard from my first P4.
The obsidian one and one of the 2 standard can't be recognize from Phantom.
The battery switch on, drone power on, but I saw ''Cannot fly'' advise.
Someone told me about a battery presence sensor, someone know where is it and how to cheat?

Have you tried updating the battery firmware?

Yes,
updated on all recognize batteries, but without any success :-(
However, in case of bettery firmwre problem the system say ''firmware inconsistency'' in this case don't recognize the battery, plugged in.

Kiko977 Posted at 2018-7-28 03:06
Yes,
updated on all recognize batteries, but without any success :-(
However, in case of bettery firmwre problem the system say ''firmware inconsistency'' in this case don't recognize the battery, plugged in.

Are these after market batteries?

ATJ has probably solved your problem.  I'm betting too that these are not original DJI.

Nope guys, are all original DJI batteries.

Hi. I am sorry for the inconvenience. May I know when and where did you purchase these batteries?

DJI Stephen Posted at 2018-7-28 07:37
Hi. I am sorry for the inconvenience. May I know when and where did you purchase these batteries?

Hi Stephen,
thank you for your reply.
The two batteries with problems come one from my first Phantom4  brought in Germany on July 2016 and the other is a gift from a bad lucky friend that lost his Phantom 4 Obsidian and give me his extra battery.
All 5 batteries are original DJI parts as you can see by the picture.
on the left the 2 "bad" on the right the 3 fine.I used the two ''bad'' batteries with my last Phantom 4 Pro without any problems.

Seeing this many times now........I understand there is a contact point on the bottom rear of the battery bay.  V2

Watching a vid from another thread on the same subject,  the guy puts a small piece of foam tape on the contact.......solved the problem repeatedly.

SO, I would suspect the tolerances between battery thickness has something to do with this issue.

Randy

rwynant V1 Posted at 2018-7-28 16:23
Seeing this many times now........I understand there is a contact point on the bottom rear of the battery bay.  V2

Watching a vid from another thread on the same subject,  the guy puts a small piece of foam tape on the contact.......solved the problem repeatedly.

Hi Randy,
I think the same if one battery had a bit more tolerance, probably Phantom don't recognize it.
Have you the link to this video? I have tried to search for it without success.
Thank you so much for your helpful reply :-)

Randy's solution works!
With a bit of tape, the battery is recognizable by the Phantom and everything goes well.
This can be used also by DJI's guys as a reference for modifying the future versions.
Thank you again.

Or u can just put a piece of thick tape or sticky foam on sensor...has to be small and sit right on it

Seems to be an error with the battery sensing system on some Phantom 4 Pro V2.0. It is very unfortunate, but sometimes this happens. I know from experience the tape trick works. But if not I suggest you open a ticket with DJI Support.

It's always irritating that such a small error (which is probably an easy fix from DJI side), can cause that much trouble.

Good luck and happy flying (soon)!

DJIJAKOB Posted at 2018-7-30 06:33
Seems to be an error with the battery sensing system on some Phantom 4 Pro V2.0. It is very unfortunate, but sometimes this happens. I know from experience the tape trick works. But if not I suggest you open a ticket with DJI Support.

It's always irritating that such a small error (which is probably an easy fix from DJI side), can cause that much trouble.

Totally agree Jakob,
tape works, I have tried this morning with success, the only things occurred was that in the middle of the flight, also the rear leds turns red, I immediately landed to check the possible error and the app, once the drone was landed and with motors disarmed, sign again the problem, solved again with an energic push of the battery.
It's so frustrating, however,  that I have to fix a €1600 with tape!!
Hope that guys from DJI here can forward this message to technitian to solve the problem in future models.

Kiko977 Posted at 2018-7-29 00:06
Randy's solution works!
With a bit of tape, the battery is recognizable by the Phantom and everything goes well.
This can be used also by DJI's guys as a reference for modifying the future versions.

That is NOT what I meant.

There is a contact on the aircraft......aircraft sitting on the table.....no battery.....locate the battery contact.....on the floor of the battery compartment......it's actually a switch.
When the battery is inserted and locked, it is supposed to push that contact down, showing the battery is properly inserted and locked.

The picure should NOT be done......that will put undue pressure on the locking tabs and try to push the battery back, away from the electrical contacts.

Randy

Do you mean this one?

YUP,  that's the one........Take that tape off the end of the battery.

One other thing for the masses........when plugging in your battery.....use 2 fingers to squeeze the top and bottom clips down and push into place.
They are only plastic, and will wear down over time when simply pushing into place.  That wear may ultimately cost you your AC due to disconnect.  Once the battery is in place, use 2 thumbs to give a push on the smooth portion of the battery, pushing the battery in.

One of the dealers here in San Diego suggested that.......I believe it's a good practice.

Randy

Great recomendations !
Thank you so much Randy!

rwynant V1 Posted at 2018-7-30 10:52
YUP,  that's the one........Take that tape off the end of the battery.

One other thing for the masses........when plugging in your battery.....use 2 fingers to squeeze the top and bottom clips down and push into place.

I read this the other day and tried it out while inserting a battery for my flight tonight.

I actually got the error message of no battery detected when I tried this method.

Removing and inserting it and letting the battery snap into place removed the error so I could takeoff.

hi.. we've bought a few units of Phantom 4 Pro v2.0.. and 2 of them have this issue. Can we get a replacement unit for the 2 units that are having this issue?
because solving the problem by putting a tape or small foam on the sensor is not really a solution. To me this is a manufacturing defect.
DJI should do something about it.
Any idea of what I should do to get a replacement unit?

I had same problem.. P4P v2.
Sent in to DJI and all good now.
Unit was replaced under warranty.

Notice the slightest movement / vibration could cost you.
Also notice how the second battery had quite a bit of play without any apparent reason or cause.

Version 2 introduced a new battery sensor that can tell if battery is in or out. Perhaps this is malfucntioning?

Anthony8858 Posted at 1-31 07:42
I had same problem.. P4P v2.
Sent in to DJI and all good now.
Unit was replaced under warranty.

I have a brand new P4P v2.0 that I bought last week that seems to have the same problem. Once the battery is firmly in place, a bit of up pressure like Anthony's video and I hear a click and the battery has movement up and down. Can someone confirm if this little bit of play is normal and the issue lies with how much contact the sensor switch is getting? I hate to return the aircraft for an exchange if they are all like that because it is almost 2 hour drive each way?

VictorCholtco Posted at 4-16 12:06
I have a brand new P4P v2.0 that I bought last week that seems to have the same problem. Once the battery is firmly in place, a bit of up pressure like Anthony's video and I hear a click and the battery has movement up and down. Can someone confirm if this little bit of play is normal and the issue lies with how much contact the sensor switch is getting? I hate to return the aircraft for an exchange if they are all like that because it is almost 2 hour drive each way?

I will say that the replacement unit had a little play.
The culprit is the sensor clip on the bottom.
If the play is enough to disable the battery, then it's a problem.
I also noticed a little more play on one battery over the other.

I've since sold the replacement P4Pv2 and kept my Mavic Air for fun

Anthony8858 Posted at 4-23 16:00
I will say that the replacement unit had a little play.
The culprit is the sensor clip on the bottom.
If the play is enough to disable the battery, then it's a problem.

Thanks for the reply. I returned the Phantom to the store and purchased a second. The second one seems to have less play for sure. There is just a little bit of up and down movement when I press up on it.  On this replacement Phantom, if I casually insert the battery firmly, it engages the sensor fully and I do not get a battery error unless I press up hard on the battery and cause the movement.

Been flying my P4Pv2 for about 2 years now. Many great flights with the use of 3 batteries.

After inserting a newly purchased fully charged battery into my drone I receive the message "Cannot Takeoff. Ensure the battery is properly connected". At first I thought I had a faulty battery, but no!

And yes, like many others, it is due to the battery not fully pressing the little switch on the base.

But the following is what I found to be the main fault, apart from the typical excessive clearance between battery and drone that several others have noted, with up and down movement.

On the rear internal faces of the battery compartment, there are several ridges in the molding which are supposed to keep the spring loaded plastic latches of the battery at the exactly correct distance to the switch so that the switch functions correctly.  After many insertions of batteries, these ridges over time have been sheering off, causing the battery to sit back away from the switch.

Very disappointing.

What made matters worse over time was as the batteries got reinserted, there was also wear on the battery locking latches caused by the ridges in the battery compartment which also adds to increased distance from the battery latch to the switch. See the attached photos showing a brand new battery and another older one I've used many times which shows this wear.

I've also attached a clearer photo (without shadows) of the worn down battery compartment ridges.

My biggest questions are, if I don't get an error before starting to fly, then I take the drone up 120 meters in the air and the battery moves in mid-flight a little and brings up the error that the battery isn't inserted properly, what will happen?
Will it try to RTH?
Will it try to land straight down?
Or worse, will it drop from the sky?

As a manufacturing engineer for 40 years, I firmly conclude this is a design flaw that should be rectified.
The way the battery clips in should never have had the chance to cause this wear.

Brett Walsh Posted at 5-7 19:27
What made matters worse over time was as the batteries got reinserted, there was also wear on the battery locking latches caused by the ridges in the battery compartment which also adds to increased distance from the battery latch to the switch. See the attached photos showing a brand new battery and another older one I've used many times which shows this wear.

I've also attached a clearer photo (without shadows) of the worn down battery compartment ridges.

The whole design of the battery and receptacle for the P4 is severely flawed, not only with regard to the locking clips, but also the poor electrical plug and socket design. The previous P3 battery had large spade type connectors that had a definite wiping action when mating, and the ability to carry large currents. The P4 used a smaller cross-section square pin and socket design that is not intended for high current, and it frequently fails to engage properly, making a resistive joint and overheating. This often resulted in the plugs and sockets melting from the heat, and failure of the power connection. That, in turn, resulted in the loss of the aircraft.

Geebax Posted at 5-7 20:12
The whole design of the battery and receptacle for the P4 is severely flawed, not only with regard to the locking clips, but also the poor electrical plug and socket design. The previous P3 battery had large spade type connectors that had a definite wiping action when mating, and the ability to carry large currents. The P4 used a smaller cross-section square pin and socket design that is not intended for high current, and it frequently fails to engage properly, making a resistive joint and overheating. This often resulted in the plugs and sockets melting from the heat, and failure of the power connection. That, in turn, resulted in the loss of the aircraft.

I totally agree!
This melting of the terminal block has also happened to one of my batteries. It has also caused the actual electrical connections to fuse into the plastic terminal block rendering it useless.
See photos

Edited post to also include a photo that shows the melting around the spade connections of the terminal block inside the drone's battery compartment.

Mine does the same thing.  I found that if you put the battery in and then firmly push the end of the battery down towards the ground, the error message disappears and you can launch.  I wouldn't mess around with putting tape near the terminal, that seems to be asking for trouble.

Can someone explain to me why the attached photos which I had included in my last 3 posts here were removed?

Brett Walsh Posted at 5-11 04:33
Can someone explain to me why the attached photos which I had included in my last 3 posts here were removed?

The photos open normally here for me.

P4P+_Brazil Posted at 5-12 04:17
The photos open normally here for me.

Ok, they're showing up again now.

Anthony8858 Posted at 2019-1-31 07:42
I had same problem.. P4P v2.
Sent in to DJI and all good now.
Unit was replaced under warranty.

For those who are interested, this is a simple, safe and sure way how I overcame the the battery sensor issue, where the sensor wasn't always detecting when the battery was fully inserted.

As the sensor switch only has a very small physical operating distance and requires to be pressed straight down (vertically) to activate, it is essential the battery has zero "up" movement.

This method removed any upward battery movement and ensured the battery is in full contact with the sensor at all times.

I cut a strip 19mm (3/4") long of Permastik Indoor Double-sided acrylic foam mounting tape which came in a 12mm (1/2") wide roll. This tape has excellent adhesiveness.

A little rubbing alcohol first on the top centre plastic strip of the battery ensured a nice clean surface for the foam tape to adhere to.

I then simply stuck the tape to the battery, but made sure that the slippery removable strip was left on the outer face of tape.

This worked perfectly. It removed the battery movement and overcame the sensor problem and does not interfere with any part of the drone or functionality.

Hello ! Please I am new here but I need technical explanation and assistance.  I have just started reseting and repairs dji batteries.
I swapped bms from a phantom 4 battery with a voltage 13.4v to another phantom 4 with battery voltage of 16.4v. But when I connect this to ev2400 module using Texas instrument software, the battery would not be recognized, but if it does, the cells voltages are looking some kind of random and unacceptable. If I refresh the whole data wipes, for data to be read again i would have to press the power button and quickly refresh the software, then same random cells voltages appear again.
But if I use this same bms on the 13.4v cell pack it is well recognized by the software.  Pls what is the problem here and the solution. I am new in repairs of these batteries

I have tried like two working bms on that same battery pack of 16.4v it does same thing.

How to overcome the Fail safe Bad Battery problem and how to disarmed this

Aditi Roy Posted at 11-2 22:34
How to overcome the Fail safe Bad Battery problem and how to disarmed this

Hi there. According to India Import Policy, Drones are 'prohibited' except for R&D and defense use. There are no DJI Authorized Retail Stores in India to sell drones. Simple consultations is available but aftersales repair service cannot be provided. Hope for your understanding and patience.