Putting in a new battery - does it matter which post I attach first?
Doesn’t matter, but generally safer to do positive first in case your wrench makes contact with ground.
Disconnect the negative first.
Connect the positive first.
That’s the way you always do it.
While it technically doesn’t matter, you do it this why because you’ll have a short to ground if you connect the negative first and then you go yo put the positive on and your wrench touches something metal while it’s on the positive post. Been there, done that. I don’t forget which order anymore. If the negative is disconnected and you do this, nothing happens, there’s no circuit to short.
i agree that
if the car is a negative ground (USA) then connect the positive first.
the non-grounded terminal is the first to connect.
Thanks guys - knew there was a particular order but couldn’t remember it.
Put in the new battery, positive first, then negative - no sparks or acid explosions- turned the key and a surge of power! Thanks, all.