How do I test to see if my alternator is bad?
An illuminated dashboard light can indicate a problem with an automobile charging system. However, a very simple way to check if the alternator is working is to run the car and disconnect the positive terminal of the battery. If the vehicle stops running, then you probably have a bad alternator.
Can you test an alternator without removing it?
Professional repair shops have such equipment, as do many auto parts stores. Best of all, most auto parts stores will test your charging system with the tool for free. You don't even need to remove the alternator from your car—the tool allows for in-vehicle testing.
How do you check an alternator with a screwdriver?
Place the metal end of the screwdriver near to the nut on the alternator pulley. You find a strong magnetic force immediately pulls the screwdriver towards it, even if the screwdriver is a reasonable distance away, if there is alternator field current. This means the alternator is operating correctly.
Related Question How do you check if an alternator is working?
Can an alternator stop and start working?
A faulty or dying alternator may only work in fits and starts. As a result, the alternator may not have what it takes to keep your battery fully charged — even with your engine running. As a result, you may find your car stalling out at odd times.
Which battery post do you disconnect to check alternator?
Do I disconnect the positive or negative to check the alternator? Disconnect the negative battery cable before testing an alternator. Instead, use a voltmeter to perform a basic and safe test.
What does it mean if your car won't start but the lights come on?
Broken or Damaged Ignition
If your headlights can turn on, but your car won't crank, that means that your battery is charged, but either the starter or ignition is the problem. If the starter or ignition is the problem, a starter engine can be jumped by using a charged battery.
What is wrong when you turn the key and nothing happens?
If nothing happens when you turn the ignition key to the "Start" position, it means that the starter motor doesn't turn over the engine. Most commonly this could be caused by a dead battery; read above How to check the battery.
Why wont my car turn over but I have power?
If you turn the key and can hear the starter motor trying to turn the engine over, the lack of power is likely caused by electrical issues such as a weak battery, dirty battery terminals or a worn starter motor. If you're still not having any joy, it may be a problem with the battery terminals.