There are times when the alternator will test out fine as far as amp output and voltage output but if your alternator has a weak diode(s) it may trigger the light to go on. I hate to say you should replace the alternator, but your charging system is pretty much self contained in your alternator so I believe the problem is in fact in your alternator. Good luck.
check fan belt is not broken or loose and check alternator
Usually when the battery light comes on its the Alternator, or a bad wire from Alternator to battery, but id check Alternator first.
You possibly have a loose alternator belt or the alternator is weak. Check the voltage at the battery with the engine running. It should be 13.5 ? 16 volts. Any less and the alternator is weak and needs replacing. Also make sure the connections at the battery are clean and tight.
There should be a plug on the side of the transfer case about half way up the side. Take the plug out. If oil comes out... it's full!
most likely its your alternator that's not charging your battery like it should causing it to turn on and off. A good way to check that is by going to your local auto zone and asking them to check your alternator to see if it creating a high enough charge.
Voltage regulator is in computer. Check Alternator, then check computer
have an alternator, battery, and electrical check to find out what the problem is. battery may not be taking a charge, or the alternator is not putting out enough voltage.
i dont know about the oil and brake ...but brake and battery light comes on you should check the alternator for proper charge
The check gauges light comes on when one of the gauges is out of its safe range. It could be the alternator over or under charging, oil pressure low, or the engine overheating.The check gauges light comes on when one of the gauges is out of its safe range. It could be the alternator over or under charging, oil pressure low, or the engine overheating.
Change your alternator
alternator, or a wire to alternator loose
Generally a rebuilt one comes with a lifetime warranty, so if you are doing the work yourself, feel free. It won't go out.
Check all of your connections from the alternator, see if the are loose or corroded. Make sure battery cables are not loose or corroded. Check the battery ground wire connection to the body of the car also. If everything appears OK you will need to test the alternator output or have it tested. You may need to replace the alternator or voltage regulaor.
Battery light usually means alternator not charging. Most common solutions would be be a bad alternator, bad connection, or loose alternator belt. If the battery and alt test ok than check the connections to the alt. You may also have a battery drain (something that is staying on and killing the battery)
The low voltage light should come on if you have a bad alternator. Without a good alternator, the battery will die causing the low voltage.
check the alternator and battery.
Drive to your nearest Auto Parts store and have them check your charging system. sounds like your alternator may be going bad. Check to make sure it is charging right. The alternator needs to put out atleast 14 amps to suffice for the engine to run properly. Might have a bad alternator.
The check gauges light comes one when one of the gauges is not in the safe range. It could be an engine overheat, low oil pressure, or the alternator over/under charging.
If the light comes on and its an auto tranny you need may need a new alternator. i had the same problem. the alternator was drawing power from my battery and o i didnt have enough power for my auto tranny
Is this a Ford? (have had some problems by not using factory rebuilts)Check alternator outputShould read approx. 12.8 without engine runningShould read 13.8-14.2 with engine running
It could mean a few things. There's a voltage range in which that light stays off, which seems to be between 11.5v and 14.5v. The light comes on when you're either above or below that range. Start by checking the alternator fuse. If that's good, and it almost always is, do a voltage test. Too low and the alternator is probably bad; too high and the voltage regulator went out. (Which is basically the same thing, since the VR is inside the alternator case.) Check to see if alternator is charging battery. With volt meter connect to battery and vehicle not running check voltage - start vehicle and observe volt meter should be around 14.2 volts - if no different running or not or if lower with vehicle running alternator is not charging battery and should be replaced. If alternator functioning properly it is probably just the "trigger" wire on alternator.
the light comes on when the alternator is bad or your regulator has gone bad. some regulators are built into the computer.
Could be that the alternator is not charging the battery properly Check with a voltmeter A fully charged battery should read around 12.8 without engine running With engine running voltage should read around 13.8-14.2 The most likely cause is a broken alternator drive belt
Try an auto parts store, sometimes they will check your alternator and battery for free.
It's the Generator (or alternator, depending on what your car has) light. If it comes on, the car isn't charging. The most common reason a VW stops charging is that the alternator belt broke. This belt drives the cooling fan so you need to get to the side of the road and check the engine if this light comes on.