Alternator?? 2000 S-10

[sumj4585]

My battery light came on today...so I changed the battery. The light is still on. My wipers seem to be running slow too. My headlight are still bright though. Is this my alternator?

[robinson52]

A good and easy way to check ur Altenator is to start the truck and pull one of the battery cables of if it dies its ur altenator if it continues to run its summthing else

[mrmikey]

That's also a good way to fry the altenator and possibly other electronics. The voltage spike created when you disconnect the battery cable could be as high as 3-400V, low voltage electronics wouldn't stand a chance. If the altenator is working and you disconnect the load the output goes to max. Same as going up a hill with your foot to the floor and putting the clutch in.
Do yourself a favor and have the output checked properly with the proper gear..Mike

[Joe Wilson]

Originally Posted by mrmikey

That's also a good way to fry the altenator and possibly other electronics. The voltage spike created when you disconnect the battery cable could be as high as 3-400V, low voltage electronics wouldn't stand a chance. If the altenator is working and you disconnect the load the output goes to max. Same as going up a hill with your foot to the floor and putting the clutch in.
Do yourself a favor and have the output checked properly with the proper gear..Mike

On my 98 S10 the gauge tells what voltage it is putting out. If you don't have a gauge use a multimeter and check the battery voltage when the battery cable (-) is disconnected (engine off) and then check it when it is connected and the engine running. If it is less, you probably need an alternator. It should read about 14 to 15 volts.

[sickcallawayc12]

Battery light comes on because essentially means the battery isn't being charged. In most cases its indeed because of a faulty alternator.