Lmm won't start?

[t2timmy]

Correct. Always do 2. If not the used battery will take out the new battery quick.

Ahh yes! Makes Sense. Thanks!

 

[MACKIN]

Yup always replace both .

 

[Kappa9012]

what he said... i actually killed a brand new battery in about a week because the old battery was completely shorted, and I didn't replace it right away.