Find a volt meter, check the battery voltage with the engine stopped, it should be a around 12 V. Now start the engine and the voltage should be around 13.5 V. If the alternator isn't putting out about 13.5 (+/- .5 V) the replacment alternator could be bad or you might have a bad connection somewhere.
The battery has a temperature sensor. If it was left unplugged, the battery light will still be on
This is not a battery problem. Your charging system, the alternator, is not putting out enough juice to charge the battery until you reach 4000 rpm. Have the alternator and charging system checked.
Go to auto zone and have the alternator checked out. even a new one can be bad.
you may need to go to your local shop and if they are equiped with one get them to attach there scanner to the vehicle and clear the codes for you.
Is it new? if it is it's not the battery. If it's really old your battery most likely is leaking.
What is the chrage when the vehicle is on? It should be around 15-15.5v
The most probable cause is a bad connection somewhere in the alternator > battery circuit. Check if the alternator is operational. Clean all contacts with a steel brush.
It could be your alternator is going bad
means your battery isn't being charged by the alternator. What originally seemed like a flat battery being the problem, would more than likely be the alternator at fault, which will drain the battery, not keep it charging on the move, hence, battery light displayed on your dash. Before jumping to the spares shop, check all the connecting wiring between these components, in case of any loose connections
does the kia have a remote voltage regulator
on my old 1.2 clio the battery light came on as there was fault with the alternator and it needed replacing. As far as i know the battery light comes on when the battery is not charging or there is a fault with the battery.
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