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Battery Light On in Car While Driving

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The battery light on in car while driving means that the charging system has fault. The most common problem is that the alternator is faulty or the alternator belt is broken.



When the ignition is turn on the batteri light will be lit for approximately 3 second for self-detection and then go off after the self-detection is completed. If the motor fails to charge the battery, the indicator light will be continuously ON. If this warning light is lit during the driving process, you should stop your car as soon as possible and turn off the engine.

Possible cause why battery light on in car while driving

1) The alternator belt is damage.
2) The alternator is faulty.


Car troubleshooting

Your car has many electrical devices, such as the starting system, lights, radio, etc. These devices are operated by electric current supplied from the battery and alternator. The amount of power generated depends on the alternator specification and engine speed.

Power generation is automatically controlled according to the battery condition and the vehicle electrical consumption (load) at a specific time. Generally, when the engine runs at idle the battery discharges, and as the engine speed increases the battery is charged by the alternator.

When your battery warning lights on the dashboard come on while driving two reasons will cause this, first is the alternator belt is broken and second, the alternator failed. The alternator is being driven by the engine using belts for the purpose of supplying charge on the battery and provides electrical power on all of your car accessories.

If the battery light comes on while driving it means that the alternator is not generating electrical power for your car and all the car accessories will draw power to the battery until the battery also loses power. Now why the alternator is not supplying electrical power to the battery and accessories?

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Two reasons are causing this, now pop up the hood and look into the alternator. Check if the alternator belt is damage if the belt is intact then the problem is the faulty alternator.

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What to do when battery light came on

Damage belt

Locate the alternator and check for the belts, If the problem is the damage belts just replace the alternator belt to fix the problem, you may do the replacement yourself.

Faulty alternator

If there is a problem with the alternator for some car, it can cause the car to stall. In this case, have your car towed to a shop and as the mechanic to check the alternator. The most common cause of alternator fault is a worn carbon brush just replaces the brush and the alternator is good to go. If the brush is in good condition the possibility is that the diode or the wiring inside is damage, in this case, replace the alternator with new or rebuilt one to fix the problem.

Car Battery Light on and off While driving
The battery light comes on and off while driving as a result of slipping alternator or failing alternator, do a simple test to find out. Read more » Car Battery Light On and Off While Driving



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