0
Any Auto Parts store can check the charging system for you. Testing the alternator is simple and basic. You need to check the voltage and amperage output. The voltage is easy enough to check with a voltmeter. If the voltage is between 13.5 and 14.5, engine running, it's a good bet the alternator is good. To check the amperage output, you'll need some special equipment. You'll need an ammeter and a load tester to check the amperage. I would let an Auto Parts store run that check as they have the equipment.
Wiki User
∙ 16y ago
Wiki User
∙ 14y agoUnless your car is from the early 60's or older you don't have a generator. You probably have an alternator. You can test it as follows, using a digital volt meter connect it to the battery and take a reading before starting the vehicle. The meter should read 12.68 volts if the battery is fully charged. You need the battery fully charged to get an acturate reading of the alternator output. Next, start the vehicle and take a reading at an idle with no accessories on, you should have a reading of 14.5 volts (plus or minus .2) if it is healthy. Next, turn on some accessories such as the heater motor on high and the headlights. The volts should not drop below 13.8 if everything is healthy. If the vehicle doesn't reach those readings your alternator is probably bad.
Wiki User
∙ 13y agoTake a volt meter and check voltage at battery terminals. First test voltage with engine turned off. Then start the engine and test voltage again while running. Battery voltage should always be higher when the engine is running. Battery voltage should never fall below 12.5 volts or higher then 15 volts, with engine running on most cars.
Some auto part stores will test your charging system for free.
Wiki User
∙ 13y agoOne can test an alternator while it's still in the car as long as the car runs. Use a volt meter across the battery terminals while the vehicle is running. The volt meter should read 13 to 14 volts in a 12 volt system. If it's lower your alternator isn't charging sufficiently. Have a friend push the accelerator and hold the car at 2000 rpms and test it again. You might try this at higher rpms as well depending on where your vehicle redlines. The voltage should not exceed 14 volts; if it does your voltage regulator is bad.
Wiki User
∙ 13y agoIf you can jump it off and it turns over and starts, but dies when you disconnect the jumper cables, then it's more than likely the alternator.
I just had to replace the one on my '93 Isuzu Trooper.
Wiki User
∙ 16y agoTake it out, and to the nearest Autozone and they will test it free of charge.
Wiki User
∙ 16y agothe battery will not charge.eventually when battery is flat the car will not run either as both battery and alternator ,togeher complete the electrical circuit
Wiki User
∙ 15y agoI pulled the negative cable from the battery with the truck running and the engine quit. Is this a test to see if the alternator needs to be replaced?
Wiki User
∙ 16y agoShops like Advance will test it for free.
Add your answer:
Earn +20 pts
Why does the the engine shut down when the battery cable is removed on your 1993 ford thunderbird?
The alternator is bad. The engine is running off of the battery and when you take the cable off it has no electrical power. If the alternator was working, the car would keep running. Be advised, doing this can damage a healthy alternator. This is not a good way to test the system.
How do you test an alternator on a 1996 Saturn SL2?
TAkeit to the Auto Zone store and they will check it free.
I have a 2003 Chevy impala how do i know if i have a bad battery or bad alternator?
To test the alternator if funds are low, let the motor idle and remove the negative battery cable, if the motor dies its probably the alternator.
Why is my 1990 Chevy van G20 alternator not charging and is not getting power?
The alternator is not getting power? At any of the wires or just the main/largest one? If you are testing the large wire, this is the output side that runs to the battery. If there is no power in this wire where it connects to the alternator it must have a bad connection at the alternator or at the battery or a break somewhere in between. If there is power there, I would look at the fuses.
MY car will start when jumped but sometimes start and die and the battery will not keep charge could this be the altinator?
could be the alternator. could be the battery, the alternator charges the battery but does not stop the battery holding a charge.could also be a bad starter motor. take alternator off and have it tested. most places will test for free
What do you do with the extra alternator wire on the 1986 Ford Escort plug there are four wires and new alternator plug has three?
I assume your talking about the rectangular plug right at the alternator, and that your new Alt came with a short repair harness, the 2 heavy wires are BAT and the slim and likely white one is Tachometer AC sense, likely that 3 of the old ones were Bat test the old connector with a test light to see which of them have power to them.
How can you test alternator for 2002 ford escape without scanner?
Easiest test is to use a voltmeter. Engine stopped , voltage about 12 volts Engine running, voltage about 14.7 volts.
How to test 1982 Ford f-150 charging system?
new alternator not charging the battery
Cylinder not firing on 1996 Ford Escort?
Bad spark plug? Bad plug wire? Do a compression test
How do you test lawnmower alternator output?
Just hold the plug wire and pull the starter, you'll know if it's good.
Dodge avenger battery dead?
Charge it, replace it,test the alternator,Charge it, replace it,test the alternator,
Why is my 2001 Ford Ranger is losing amps and the battery light is flashing when it's given gas but is fine at an idle?
Many auto parts retailers will test your alternator for you without charge. It sounds like a possible diode or regulator problem meaning that you'll probably need to replace the alternator, but you won't know for certain without testing it.
How do you change the alternator on your 1996 Ford Escort?
ask your Dr for a med for high blood pressure and test you blood pressure
Why won't a 1993 Mitsubishi Elipse keep running after the alternator was changed?
if a battery has a bad cell it wont hold a charge, but it could also be the alternator or the plug, i had a problem with the plug and had to change it from a junk yard, but before you do that i would check the easy parts first i.e the battery,then the cables, then the tension of the alternator belt, and finally the alternator itself along with the pigtail get a volt meter and test the current while the car is running, if it reads 13 to 14 volts the alternator is working and if it reads bellow 12 it is the alternator or plug. aojedamCheck your battery, it might be worn out and not able to hold a charge from the alternator.
What is the EEC test box near the power distribution box on a 1995 Ford explorer?
What does the EEC test port have on the plug end and what does it do
How do you know when to replace the alternator when not running?
The alternator must be running to test without disassembly. If you remove it, many auto part stores will test at no charge. One test is a voltage test. Start the engine and use a multimeter to check the voltage at the battery. It should read between 13.5 and 16 volts. Any less or more and the alternator is bad.
Why wont my 99 Ford Contour start if battery and alternator test fine but battery light comes on and EVERY light in the car slowly dies down followed by car turning off?
If alternator and battery test fine- then you may have a bad fusable link not allowing the alternator to charge the battery
