"The battery is dead, you need to replace it."
Translation:La batterie est morte, il faut la remplacer.
Yes, but the meaning changes just slightly. Vous devez la remplacer indicates that the speaker is giving the responsibility of replacing the battery to a specific vous, whereas il faut la remplacer is an impersonal construction that does not indicate a specific person responsible.
True. However, I had to translate from English to French and English makes no such distinction. So I couldn't tell whether it was an exhortation for someone to go ahead and replace it or whether it was a general statement that it had to be replaced.