Dead Honda Civic, but can be jump-started. What's wrong?

Question

I have a 2002 Honda Civic. I used to drive it about 100 miles a day, but for the last two weeks, it has been sitting for a few days at a time. After those periods, it would start a little hard. Today, it had been sitting for about five days, and when I went to start it, it was totally dead... no lights, radio, nothing.

It was easy to jump start, however. Once the car is started, it's fine.

The battery is about a month old, so I don't think that's the problem.

Any guesses what's wrong?

Answer 1

If you have or can borrow a digital volt meter (or old "swing" meter, for that matter) check the voltage at the battery terminals while the car is running.  If under 13, you have a charging system problem - if over 14 you have a battery problem.  Good luck!

Answer 2

get a volt meter across your battery. run the car at about 1000rpm. if the voltage is below 13 then it is your alternator. if it is over 17 you have a regulator problem. when the engine is OFF. disconnect one terminal of your battery and measure the voltage across it. reconnect the terminal and if the voltage drops more than 2v you have something in the car on or faulty(broken wire etc). or use an ammeter and if the current is m,ore than 0.5A (engine and ignition off) then it is definitely a broken wire or a light on somewhere etc.

Answer 3

Check your alternator first, easy way to check it is to, get the car started or running, and take off your positive battery terminal, if the car is still running, then your alternator is good, if not time to replace it.

Answer 4

get your alternator checked out. your alternator charges your battery while driving if it is not charging it then you are driving on battery only.

Answer 5

My sister had a very similar problem after she got new battery installed, the problem - Dead Alternator. The shittiest part of the situation is that the old battery that she threw away, probably worked fine, it just wasnt getting charged...

Answer 6

After you get the car jumpstarted, leave your car on idle and use a multimeter to measure the voltage across your battery terminals.  If the result is less than 13.5 volts then diodes in your alternator have burned out which will reduce it's ability to recharge your battery.

Visit your local auto parts store and buy a new alternator.  If you have tools to help you replace your bad alternator, you'll save a lot more money.

Otherwise, you'll still save money if you already have the part and just find someone knowledgeable you can pay to do the labor.

Good luck!