Any help with the following would be appreciated:

Just tried charging my 4000 li-po's, but when I tried balance charging them I get a low voltage error and when I check the cell voltages I get cell 1 at 3.89v and cell 2 at 0.01v.

I suspect that they are bust, which is not good as these cells we the replacement for the first cells that went.

I doubt that one cell has really found its way to 0V without swelling, more likely a connection problem.

Firstly you could try charging without the balance lead, if one is really at 0V you should still get the low voltage error. If it charges then there must be a fault in the balance lead/connector somewhere.

It charges without the balance lead, but I am not wanting to charge too much that way.

With the balance lead on it goes:

0.01
0.04
0.02
0.01

then it errors

It's also worth saying for those who might not be familiar with LiPo's, always exercise caution. If they swell, don't charge, if they hiss or get hot, don't charge them. Never use a damaged set of cells and if you have a wiring issue, make sure you get someone who knows what they are doing to sort it out.

Almost certainly either a charger fault or wiring fault.

I can take a look in the morning. I've got some Demon 4000s for my E-Revo, the balance has been rock solid with or without the balance lead, I wouldn't worry about charging them without the balance lead if they have otherwise been regularly balanced. You could check their balance with a meter if you can get onto the balance pins, you have to be very careful doing that though because you could short out the cells if the probes touched each other. I've got a balance lead for my charger, so I can check them for you if you want to wait until the morning, if they're at 3.9V they should charge in 30 min or so.

Does your other pack charge okay? I guess if it does that rules out the charger and it must be that battery's balance tap.

They charged fine on a normal charge when I tested them for 60 seconds and they were charging at 5a and 8.40v, so this means the cells are fine. I guess that it mist be a balance lead issue internally.

I will let you have a look in the mornign before I proceed with charging them any further.

Any news from Nick yet?

Not had a response yet about the charger, but I have just looked at the instructions for the charger and the warrenty only lasts 30 days. So it might be expensive to fix.

Any more news?

I have contacted Schumacher and I am waiting for a response. I might have to borrow a charger of someone at some point so I can do a quick balance charge of my cells.

I seem to remember your cells had gone a bit out of balance when we looked last time, we could put them on mine first thing on Sunday to get them balanced. From what I've seen, once they're in balance, if you charge without the balance port they're unlikely to move away from being balanced for some time. If you drop them off at mine sometime I can do them before the meeting.

Quick update on the charger situation. Nick from demon said to contact Schumacher regarding the charger and they have offered to either repair of replace the charger at no charge which is good news.

Thanks for the offer of balance charging my cells, can I drop them off sometime today? Send me a text with whats best for you.

Good to see Schumacher are sorting it out.

Your packs balanced out okay. The 5000 was only a little out and the 4000 a little more. They were only out by 0.04V, seems to take my charger ages to sort it out, got there in the end though. Be interesting to check them after you've charged them twice tomorrow to see if they've held their balance.

Top Man, much appreciated!!!!!

See you in the morning.