Stihl MSA AP300 flat battery reboot

[derwoodii]

My Stihl MSA AP300 battery had gone flat, i suspect as left sitting idle on cold shed shelf it had dropped to less than 6 volts and would not recharge in cradle.

I explored some yotube vids where operators hooked up MSA battery's with jump start wires and rebooted dead battery.. But as i could not work out which blade terminal was + or - and bit fearful of fizz flash or bang! I took it to a specialist battery store the chap checked tested & put it on his (defibrillator) battery charger and rebooted it.

Yay brought back to life this saved me some bucks.

 

[Syflan]

Bleep! The lengths manufacturers go to prevent owners repairing their own equipment is maddening. (find Louis Rossmann on youtube). I searched the internet for a pinout diagram. No luck. Personally, I have AK series batteries, but I think the pinout is the same. Anyway, I'm peeved enough to make the effort.
If you want to try this, you can use a welder set for DC, 36V to zap the battery.

 

[OM617YOTA]

Is there a reason you can't hook a multimeter up and see what the polarity is? Has the BMS shut it down entirely , so there's no voltage at all to be read?

I have a benchtop power supply that I used for top balancing my solar power cells, and it would probably work for this also. One of those things I put off buying until I had a real need, and now that I have one, I seem to use it all the time.

 

[derwoodii]

Is there a reason you can't hook a multimeter up and see what the polarity is? Has the BMS shut it down entirely , so there's no voltage at all to be read?

I have a benchtop power supply that I used for top balancing my solar power cells, and it would probably work for this also. One of those things I put off buying until I had a real need, and now that I have one, I seem to use it all the time.

I dont have multimeter only a probe current tester that pins would not fit into the battery blade gaps plus im not super confident playing with stuff i dont know so left it to shop battery specialist. The Stihl shop tested the battery found it cell continuity ok said it read 6 volts so below reboot level.

 

[stihltech]

Reminds me of the revival of a dead Dewalt battery. Charger has to sense enough voltage to recognize the battery is present to charge.

 

[OM617YOTA]

I dont have multimeter only a probe current tester that pins would not fit into the battery blade gaps plus im not super confident playing with stuff i dont know so left it to shop battery specialist. The Stihl shop tested the battery found it cell continuity ok said it read 6 volts so below reboot level.

Multimeters are incredibly cheap, and good for a pile of different things. Surprised you don't have one.

 

[derwoodii]

Multimeters are incredibly cheap, and good for a pile of different things. Surprised you don't have one.

Yeah true i should buy one, i bit flummoxed with all settings complexity of them a few minute youtube schooling up is all i need