Battery Cell 2 Voltage, and Battery Capacity jumping around, loose wire?

[JD910]

my battery level is jumping around, 85%, 45%, 4%

plugged it to Escribe and voltage on cell 2 is jumping a bit also. Anyone know what the problem is?

Battery Management.csv

[Wayneo]

More info needed.
Are you the original purchaser?
Can you start up escribe, go into Device Monitor. Only click on (enable) 
Cell 1, Cell 2, Power
Take a puff. Scroll back to where the puff data is, take a screen shot/capture. Post that here.
 

[JD910]

took 3 puffs

[JD910]

no puffs. battery voltage jumps the entire time

[Wayneo]

Thanks. Perfect. And now if you were to swap cell positions in the mod?
 

[JD910]

Same thing. only let me take 1 puff before saying "check battery".  Does it with completely different set of batteries also, and both pairs of batteries work fine in other mods

[Wayneo]

Yup, not a battery problem. Open a trouble ticket with the Help Desk. Link in my signature

Unless you want to rip it apart yourself and diagnose the issue further.

[JD910]

I don't have a multimeter, but I did pull the casing apart somewhat to check for leaks and loose wires. Everything on the board and top of battery sled looks ok, but it feels like I can't remove the sled without desoldering it from the board

[JD910]

Is it possible that the battery management system is shot, or can we rule that out? j/w if I should go thru the trouble of re wiring it, or just buy another

[Wayneo]

Open a ticket. No need to buy another board or mod at this point. Your DM screenshot does NOT lead me to believe it's a board issue. 

[JD910]

well that's good news. Thanks

[JD910]

Aannnndd I don't have a receipt or order confirmation for it so they won't help me. Like really, Drone's have been discontinued for how long now? Who keeps receipts or emails for that long? Guess I'll just have to fix it myself or get someone else to do it

[BillW50]

Just as a test, can you select the battery type Power Supply in EScribe? You have to be using the manufacture's user interface to change battery type and pick a 9v power supply.

 

 

 

You have to upload changes to device of course. If it works just fine now, I believe it is either the battery wiring or the Battery Management IC. If it is the latter, you might see one cell voltage being drained lower than the other. The mod and EScribe won't see cell voltages when selecting power supply. But the one cell draining would be happening now and drain one cell down to 0.5v in a day or so.

Edited November 15, 2020 by BillW50

[JD910]

so change it to 9v, leave the batteries in and wait a day to see if one gets drained?

[JD910]

it is working, voltage is staying constant on both cell, and is firing. Battery level stays at 1% though. Will update later today or tomorrow morning after checking actual battery level.

Drone 9v power.csv

[BillW50]

22 minutes ago, JD910 said:

so change it to 9v, leave the batteries in and wait a day to see if one gets drained?

 

Yeah I only give it a few hours to see if a cell is dropping and check voltage with another mod or an external charger. Waiting a day one cell could be dead and worthless because the voltage dropped too low (I wouldn't charge a dead battery, just dispose it). The DNA also won't charge cells in power supply mode. And I wouldn't trust the voltage readings from that DNA250C until we know what is wrong.

[JD910]

Should I be using it throughout the day to facilitate the battery drain?

[JD910]

ok. I've got an external charger that shows voltage while charging, and a 250c Centaurus that I haven't used yet, so either would work. I'll check it around 3 hours from now.

[BillW50]

1 minute ago, JD910 said:

ok. I've got an external charger that shows voltage while charging, and a 250c Centaurus that I haven't used yet, so either would work. I'll check it around 3 hours from now.

Ok

[JD910]

haven't been using the mod, but just took both batteries out and put them on the charger. Both reading the same, 4.15v

[BillW50]

Ah good. There is a wire on the battery sled that should be some other color besides black or red (white would be my guess). It connects to one cell on the positive and another wire going to the other cell's negative. And it also goes to the DNA board for balancing, reading cell voltages, and charging. Sounds like something not making connection with that wire IMHO.

[JD910]

The Drone is ran in series, with both positives and both negatives on together on opposite ends of the sled. I did take it apart to check for leaks when it first happened, although could not get the sled out completely without desoldering it. on the bottom of the board where the positive and negative wires are attached, there is a wire that looks like a faded red color, I'm assuming that is probably the balance wire.

[BillW50]

As long as the faded red wire isn't connected to either the red or black. I just shined a 1000 lumen flashlight through the fake ultem and the bottom right sled has two wires soldered on to the tab. Looking through the plastic, it looks orange. But it could be very well faded red. Those are the wires you should check. One should go to the top left positive connection and the other one should go straight to the DNA board.

UPDATE: I just ohmed bottom right to top left and it is indeed a short on one of mine here. So that is correct.

Edited November 17, 2020 by BillW50

[JD910]

Great! I'll get a soldering iron and see if I can fix it! Thanks for the help!