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An alternator that is charging insufficiently won't necessarily damage a battery unless it is driven that way for a very long time. More often a failed voltage regulator ( internal in most modern alternators ) or a failed rectifier in the alternator will damage a battery.
To test your alternator you will need a volt meter. Start the vehicle and test the voltage across the battery terminals. Put the positive lead of your meter to the positive terminal on the battery. The rate of charge ( reading on your volt meter ) should be 13 to 14 volts; if it is lower your alternator is insufficiently charging. Have a friend step on the gas and hold the motor at about 2000 rpms. Repeat the test on the battery; if the voltage reads above 14 volts your voltage regulator has failed. Testing rectification from your alternator requires an osciliscope. However, normally if the rectification diodes fail your alternator quits charging and you will have determined this with your first test.
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What can cause low voltage on a 1994 Chevy Cheyenne with a new alternator and a fairly new battery?
The ignition switch may lead to low voltage on a 1994 Chevy Cheyenne with a new alternator and a fairly new battery.
Will battery idiot light come on if battery is low but alternator is ok?
No. If the alternator is working fine, the battery power is not used.
Will a bad battery cause your car to lose power at higher rpm will it idle low at a stop?
No, but a bad alternator will.
1994 explorer lights dim wipers slow and battery gauge goes to low What would cause this?
Either your battery is dead, or your alternator has failed.
Can a faulty computer cause low cold cranking amps in your 1999 dodge avenger?
The computer controls the alternator. If the charging system is malfunctioning, that could be the cause of the weak battery.The computer controls the alternator. If the charging system is malfunctioning, that could be the cause of the weak battery.
Would a bad alternator make a vehicle run rough?
Alternator versus Engine Performance IssuesIn and of itself, a "bad" alternator will not effect the engine performance.That said, IF the alternator is not properly charging the battery, and the BATTERY capacity gets low enough, then the very low power can result in very low spark production at the spark plugs, which will fail to dependably ignite the fuel, AND THEN result in "rough," or no running.So, a "bad" battery itself does not cause rough running, but can lead to battery depletion which can.
Will a 2002 chrysler voyager still run if you take the battery cables off?
Maybe. The engine computer is the voltage regulator, with the battery disconnected it may not be able to control the alternator output voltage correctly. This could cause it to go low or high.Maybe. The engine computer is the voltage regulator, with the battery disconnected it may not be able to control the alternator output voltage correctly. This could cause it to go low or high.
Why would your battery light stay on after you have put in a new battery and alternator?
The battery light comes on when the alternator output voltage is too low or too high. You have a wiring or regulator problem.The battery light comes on when the alternator output voltage is too low or too high. You have a wiring or regulator problem.
What does the Low Battery Voltage message indicate on Volvo S80 2001?
It means the battery voltage is low. Can be the battery is defective or the alternator is failing.
What could be the cause of a clicking noise in the engine of a 2002 Pontiac Sunfire?
check if your battery is low than usual ..might be alternator problem
What causes the Ford Taurus battery light to come on at low RPM?
The battery light tells you the system is not charging, if it comes on at idle or low rpm it is likely a weak or failing alternator. The idle being too low can also cause it to come on.
Why does your battery indicator show red?
Red means that the battery charge level is low or that the alternator is not charging battery properly. Check alternator, voltage regulator, connectors.
