Car battery charging problem

Thread Starter


Joined Oct 30, 2008
I installed power amplifier to my car by myself.I've checked all the audio wiring...everything is ok because the power to the power amplifier is fused and the fuse not blown.But after finish i realise the battery is charge.So i jump start from my frens car...its successfull.But i take my car for a ride as soon as started n on my blower...after 10 min the engine stopped by itself and i cnt start back because no charge in battery.Then i jump start again n drove back home...same things happen.Then i saw battery indicator is ON on the gauge.

As i know...if that indicator ON means no charging occur.So i search for any blown fuse and replace it.

Then the indicator no more ON.But the funny thing is the problem occured again.So i suspect the battery had spoilt.
1)Can the battery become spoilt if any short circuit happened?
2)What is the flow of a charging system in a car?
3)What may cause the battery dead and blown fuse?
4)Is the engine stop because not enough charge inside the battery?
5)What is the meaning if the battery indicator on the gauge is ON?

FYI:My car is Toyota Corolla SE Limited and dont have ECU.

Please share ur knowledge n experience....


I would check to see if the alternator is functioning properly.

From :

"Because your car is so dependent on the battery, all cars have a battery light on the dashboard that is designed to warn you if the recharging system fails. A simple circuit looks at the voltage that the alternator is producing, and turns the battery light on if it is low. The battery light indicates a battery charging problem. If the battery light comes on and stays on while you are driving, the most common cause is a broken alternator belt. Total failure of the alternator is another possibility.

The reason why your car can operate normally even though the battery light is on is because your car can run off the energy stored in the battery. Your car will run fine until the battery goes dead. At that point, nothing in your car will work. When the battery light is on, you can still drive your car to the garage -- you will not damage anything. But you want to get to the garage before the battery fails and your car dies."

Does everything work properly if you disconnect the amplifier?


Joined Feb 5, 2010
car starting batteries will not function properly or for very long after a deep discharge.

Starting batteries have many many, very thin lead plates. This greatly increases surface area and gives the battery the ability to output huge amounts of amperage in a short time. It also means if that discharge is continued very long the plates will be eaten away and destroyed by the action of the acid in the chemical reaction. it will form a dust that collects at the bottom of the battery and will short out the plates in the cells.

Once a starting battery has been allowed to 'die' it very seldom will function very much longer.

Replace the battery and then check the alternator output by removing the red wire from the battery while the car is running. - if the alternator is putting out voltage the car will keep running. - if there is a problem with the alternator the car will die when you unhook the red battery cable.


Joined Dec 5, 2009
Make sure your amp is turning off when the stereo is turned off and when the car is off.

If the antenna or control wire is not proper, and has voltage 24/7, your amp will continually be in use, even when your car is off. no-good.

Also, the alternator is a prime suspect.

BUT the amp draining the battery deeply can cause a weak alternator to bite-the-dust ;)


Joined May 9, 2009
It could also be that the amp is drawing current at a higher rate than the alternator can recharge the battery, causing the battery voltage to drop.


Joined Jun 7, 2009
The single largest problem in your electrical system is corroded battery termninal clamps. Make sure yours posts/clamps are clean and snug. Check your battery condition with a specific gravity tester.

If your system is constantly discharging, then you'll have noticeably less cranking power after the vehicle sits for a few hours. If the charging system is not working, you'll often find that after sitting a few hours, you get a little boost of cranking power, before it dies.

With your vehicle running, turn on your headlights and rev the engine. If your charging system is working, the lights should brighten.

If the problem occured after you installed the amp, you may have mistakenly tied into the alternator field source.


Joined Apr 2, 2009
I go with retched.

Ur are having trouble after u installed ur amp.
If this is the case disconnect it see if the battery keeps draining. If so battery is dying.
To check ur charger just connect a good DMM across the battery and see if you can get around 13.8V or more when engine is running. If not then Alternator is the culprit.

If everything seems fine. Just check the amp remote connections.
See that amp power downs when u switch off the stereo

Thread Starter


Joined Oct 30, 2008
Firstly sorry coz i forgot to mention that i didnt have chance to check my audio system coz the battery was drained out.Then after this problem occured,i disconect all the wiring that i made but the problem still occured.From all of ur guys respond....i think the problem was from alternator.But that was a new alternator....a few months old.Can the alternator spoilt because of a short circuit?


Joined Jul 26, 2010
So-called new alternators can be bad right out of the box or fail in a short time if they weren't manufactured/rebuilt properly. 99% of all auto parts stores can and will gladly test your battery and charging circuitry in a matter of minutes for free.


Joined Feb 5, 2010
check for 'pinched wiring' underneath anything you might have routed the power wires through. If the amp fuse didn't blow the short -(if there is one)- will be in the wiring. It would also be a prime suspect in the dead battery mystery as well.


Joined Jul 17, 2007
Never disconnect the battery while the engine is running!

The alternator needs the battery to keep the system voltage stable. Without the battery, the alternator can produce VERY high voltage spikes that can destroy expensive items such as your engine control unit (ECU); replacing those can break the bank!

You can use a simple digital multimeter to see if the alternator is charging. With the engine running at a fast idle, your nominal system voltage should be between 13.6v and 14.5v; some newer systems go up to 15v for fast charging of AGM-type batteries.

Alternators can die a sudden death if heavy loads are placed on them; such as jump-starting someone elses' car with the engine running. Batteries that have been deeply discharged can also cause alternators to suddenly die.

Keep your vehicle's battery charged using a commercially available battery charger. To minimize heating of the battery, use a charger rated for 6A or less. The faster you charge a battery, the more heat is generated internally, and the shorter the life of the battery will be.


Joined May 28, 2009
With the engine off, disconnect the negative lead from the battery. Connect an ammeter in series with the battery and the ground cable. This simple test will tell you if there is some kind of current draw when your car is off. Most cars will have some small current draw for the clock, a blinky LED, and maybe an alarm system. Anything in excess of 200mA would cause concern. If you do have a significant drain, disconnect your amplifier and see if that is the culprit.

Another test would be to start the engine, turn everything off except the amplifier. Do the test again (use the highest amperage setting). Test it with the amp on and with the amp off. This will tell you how much current your device is drawing. Look at your battery specifications to see if your battery (and charging system) can handle it. If not, you may want to go with a heavy duty alternator. Manufacturers use the smallest alternator necessary for the car to function properly. They seldom take into consideration that the end user will put such an incredible drain on the electrical system.

Thread Starter


Joined Oct 30, 2008
At last..its been fixed.I brought my car to wiring shop.The shop guy said the alternator faulty.I asked how u know without checking...he said he looked at the alternator and found out the winding is in black colour which means burn out.He changed a reconditioned alternator and the problem fixed.He tried many alternator but failed...the warning indicator still light up.But after the 5th alternator...he made it.But i still wonder why other alternator fails?


Joined Jul 17, 2007
Was the battery charged nearly completely before the engine was started with the new alternators?

I'm wondering if the alternators all came from the same rebuild shop, and if they are having a counterfeit part problem.


Joined Feb 19, 2009
I had to run dual alternators and a few batteries, as well as 4 0.5 Farad caps in a "Show Car" a stereo shop put in my car. (Partly Why I'm deaf these days)

Once you cross around the 1,000W RMS line (Insane loud), Alternators will start smoking unless you have at least a 1 Farad cap at the amplifiers. I'd suggest an Optima Yellowtop Battery under the hood and another in parallel near the amp. Go with 1 Farad/1kW at the amp.

You will continue to go through batteries and alternators when using very high powered stereo equipment without caps and a secondary (physically close to amp) battery, this is something your installer should have told you.
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