What should the voltage of a car alternator be?
A healthy, fully charged battery should have a voltage of 12.3-12.6V. Anything below 12.3V could indicate a bad battery or a bad alternator. Time to test the battery under load.
What does it mean when battery and alternator don’t match?
Also the voltage at the battery and the voltage at the alternator should be within 0.5v of each other. If the voltage at the battery and alternator don’t match. For example the battery reads 12v and alternator reads 14v. This means that there is an issue with wiring. While applying the same conditions as above.
How can I tell if I have an alternator problem?
To differentiate an alternator problem from the battery, you will need to use a voltmeter to check for voltage. First, turn off the engine and check the battery voltage. A fully charged battery should have a reading of 12.65 volts. Next, turn on the engine and recheck the voltage. You should have a reading of 13.5 to 14.5 volts.
Is it dangerous to drive with a bad alternator?
Driving with a bad alternator is dangerous, more so with newer cars that rely so much on electronics. And, if your car has a fully electric power steering, don’t even think about it! It becomes a serious safety hazard for you and the people around you. You will be better off towing the car to the mechanic.
What should battery voltage be when alternator is not charging?
The alternator is connected to a set of belts which when loose can cause it not to function as required. To differentiate an alternator problem from the battery, you will need to use a voltmeter to check for voltage. First, turn off the engine and check the battery voltage. A fully charged battery should have a reading of 12.65 volts.
What happens when the alternator is not putting out?
Have the driver rev the engine a little. The voltmeter should slowly climb towards 13 volts, then after a minute or so be up to 13.6-13.8. If the meter stays below 12.5 volts with the engine running at fast idle, the alternator is not putting out…Most of the time, an alternator failure will trigger a red dashboard warning light, “alt” or “Batt”…
How to test your alternator with the battery connected?
Open the hood and find the alternator. Put the tip of the screwdriver near the bolt holding the alternator pulley wheel. Nothing should happen. Turn on the car’s ignition, so the dashboard lights are illuminated, but do not start the vehicle. Use the screwdriver to touch the pulley bolt again.
What should battery voltage be with engine off?
A fully charged battery should read 12.6 volts with the engine off. The reading of 12.1 means the battery is run down a bit or is bad.