Car trouble · Won’t start / battery

My battery keeps dying

The car starts after a jump but is dead again a day or two later. Either the battery can’t hold a charge, the car isn’t charging it, or something is draining it.

Get to it this week

A starting point, not a diagnosis. Most parts stores read check-engine codes and test batteries for free.

Likely causes — tick the parts you want

  1. An old battery that no longer holds a charge

    most likely · Most people can do this

    How to check: Look for a date sticker on the battery. Most batteries last three to five years, and heat shortens that. A free battery test at most parts stores will confirm it.

  2. An alternator that isn’t charging

    possible · Doable with tools and a free afternoon

    How to check: Watch for a battery-shaped warning light while driving, or headlights that dim at idle. A free charging-system test at most parts stores will tell you.

  3. Something left on, or a small electrical drain

    possible · A mechanic’s job

    How to check: At night, check that the glovebox, trunk, dome and vanity lights all go out when closed. If nothing is left on, a mechanic can test for a hidden drain.

Be careful

Wear eye protection and gloves around a battery — it holds acid and can give off explosive gas. Take the negative (black, minus) cable off first and put it back on last, and never let a metal tool touch both posts at once.

Your car — the counter needs this

If the counter doesn’t have a part, your shopper asks them to order it under your name and messages you the order number. When it comes in, send someone to collect it.

Not quite it?

My car clicks but won’t startMy engine cranks but won’t startMy car cranks slowly when it’s cold
My battery keeps dying — likely causes and the parts · DriverRuns