Expert: Rob Painter - 8/12/2010

Question
For two days my car started with some hesitation when tuning the key.on day three my car would not start but windows, lights,and dash lights worked.Got a jump but took about four tries with the "woo-woo"sound and finally started.Drove to Auto Zone,they tested the battery and said it was bad so I bought a new one.The car will not start now but the dash lights,windows,and lights still work.Now they say it could be the starter,alternator or a wiring problem.I would appreciate your expert opinion.

Answer
Hello.

I have no use for auto zone, pep boys etc. They will sell you anything. Most don't have a clue as to what they are doing with that fancy test equipment.


We need to do a process of elimination in order to get you fixed up. The scary thing is that I can be thousands of miles away and still assist people.

Isn't that strange? It is called experience, in which these parts changers have none of!!!!!

You are going to have to get the car started first, whether with a jump or whatever it takes.

You will need a multi-meter that has volts on it. We could get an amp guage out as well, but at this moment I am more concerned with voltage.

Once running, you need to take each lead from the meter and put one on pos cable and the other on the negative cable at the battery.

While running, the voltage at the battery should be 13.2 volts or higher. If there is only 12 volts or less, you have an alternator problem.

Be sure to check all fuses before replacing the alternator.

If that checks out OK, go to the next step. Turn off the engine. Looking for a parisitic draw.

Remove the positive cable. Make sure everything is off-dome lights etc.
Put one lead at the battery rterminal and the other to the positive cable.

If you have 12v by this test-you need to remove each fuse seperatetely until you find the circuit causing the problem. For example: The meter reads 12 volts. You remove the dome light fuse and it is now no showing voltage this way.
You remove the fuse and then there is no voltage. Something is wrong with this circuit. You find the cigareet lighter are tied into that circuit. You remove the lighter and the car is fixed until you replace that lighter.

This test will also show if you have shorted wiring.

So now you have done two things to diagnose the problem.

Connect battery by removing neg cable and then reinstalling positive snd the negative cable.


Starter: Now you need to set the multi meter to amps. Place the leads on each battery cable. Have someone crank the engine. I do not have the specs for your car, but if the ammeter goes to 600 amps, your starter is drawing too much and needs to be replaced.

In fact, if you have the alternator and draw tests handled, you can be sure the starter needs to be replaced.

That wasn't that hard to do, you know much more than the idiots at autozone.

Please, if this helps you out give my answer a rating. Thanks

Rob