My new 3s lipo connected my esc some electric spark came and as dead..I checked my lipo with lipo checker it shows only 2 cell voltage..I try to charge it shows 2 cell charging.. I checked its main lead with multimeter it doesn't show any voltage  what happend my lipo..?

I am a little bit confused with this

"I try to charge it shows 2 cell charging.. I checked its main lead with multimeter it doesn't show any voltage"

What charger you are using?

B3 AC

Lipo checker detecting only 2S and all voltage is normal for 2cell

OK,
Try This with caution!

1. Identify the cell that seem to be dead
2. Use a multimeter to check that cell only
3. If you see any voltage, it is good.
4. If the voltage is somewhere below 3V the charger is not able to charge that cell!

5. Now the dangerous part: Do with caution!!!!

5i. Find a 5V/2A DC Output, a stopwatch (you can use mobile), some wire to connect the battery, multimeter.
5b. Connect the charger (MATCH THE POLARITY) with the dead cell and charge it for 15 sec. NOT MORE THAN THAT. (use the stopwatch). Then measure the voltage, if 3V or higher, you are done! Connect it with your lipo charger. It should work.
5c. If the voltage is still below 3V use the process as 5b. and repeat till it shows 3V or higher. After each charging the voltage should rise. If not rising you have a damaged cell! So no luck.


6. If no voltage shown, the possibility is internal soldering may be open (You have reported spark!) open the battery and check for that.

Is 5V is connected to balance lead of no voltage cell.  ?
Why it main lead shows any voltage..?
Is lipo checker will detect all cell even it has no voltage..?

3 S connection try with caution
don't short pins or will result in fireworks
regards

Sorry. I overlooked your last message. as lipo check shows only two cell it is highly possible that a solder joint is open.

If solder broken ...I have to open lipo and resolve it .!  is it risky..
Main lead also not showing any voltage...

No risk if done carefully. Keep in mind two things. 1. Avoid any chance of short circuit. Desolder one wire tape it then another. 2. Don't over heat the lipo while soldering. Clean the leads with alcohol or acetone first. Rub it gently with sand paper and apply good flux and solder with a good iron. A little tricky job. And yes please don't try if you are not confident in your soldering skill.

CAUTION:
IF YOU DONT HAVE EXPERIENCE WITH ELECTRONICS, ESP LIPOS, DO NOT TRY TO REPAIR LIPOs.
SO DONT ATTEMPT ANY REPAIRS TILL YOU HAVE EVALUATED THE PROBLEM.

That said, can you just connect your lipo checker to the lipo and post a video of what it shows?

Sorry..I just open it.. will u check the company soldering

As now you opened it just chk voltage at each cell.

Something seriously wrong.
Did you solder some wires, or did it come like this?
Pl post side view so we can see battery make and specs.

The wrong polarity of the balance plug is a dead giveaway.

I’ll stop here as others too are trying to help...

Yes sir I just oped it it is company soldering..its red balance wire goes to red.....its shipped from electronics comp..my 2 esc dead..

Image

Inage

What to do ..sir  its company soldering polarity is wrong....any repair is possible..

Does it?
Obviously not!

It seems wrong soldering. Check with a multi meter with individual cell leads for the polarity. It should be as per the drawing shared by Mr Ashok 2010.

You didn’t post a side view to show make and specs.
Pl do.
There are many experienced members near you who can check your lipo.

Failing that, you can send it to me...

Sorry sir its red balance goes to black...main lead

Perhaps assembled by someone locally.
Unlikely that a manufacturer would make such a mistake.

Await side view showing make and specs...

Image

Individual cell show 3.8 volts