Car battery light is on replaced alternator battery and starter and battery light is still on.

Car battery light is on replaced alternator battery and starter car turned on and stays on but battery light is still on. What else can be the problem? Help please.

My car has 250 miles.
My car has an automatic transmission.

Experienced mechanics share their insights in answering this question :
You may have a failing voltage regulator that could be allowing the alternator to supply too much or too little amperage to the battery resulting in the battery never maintaining a consistent charge as it is designed to. The voltage regulator is a unit that regulates the charging of the battery by the alternator. When the voltage regulator is not working properly, this may result in the alternator allowing too much power to be delivered to the battery resulting in damaging wires and prematurely sometimes destroying the battery. A common sign of this is usually the acid inside the battery boiling causing the battery to swell. You may also smell a bit of smoke due to things potentially getting too hot. In other cases it may result in the alternator not supplying enough power to the battery, resulting in undercharging the battery or not charging it at all. I would recommend having an expert from YourMechanic come to your location to diagnose your vehicle’s charging system.

How to Identify and Fix Common car Problems ?

Our sources include academic articles, blog posts, and personal essays from experienced mechanics :

It is possible that the problems that you have been experiencing with the bad alternators have damaged the battery causing it to be weak. This would make the Battery Light come on. It is also possible that there is a problem with the fusible link or the alternator fuse for the charging system.
Basically, the light indicates a battery charging problem. If the light comes on and stays on while driving, this means that your alternator is running solely on energy stored in the battery. If you continue driving, your battery will eventually drain and your vehicle will stop working.
Sometimes after a battery has been replaced there can be a few warning lights illuminated in the instrument cluster when the vehicle has been started. Most likely they will be a combination of the ABS, ESP and TCS lights however there may be others. The first thing to do is not panic – this is normal.
I did a bit of research and found a battery reset is required to resolve the issue. The message can reset by itself, but the car needs to sit undisturbed for at least eight hours. Perhaps with your work/driving schedule the car doesn`t sit long enough.
The red battery light could indicate a problem with the alternator, battery or other parts of the electrical and charging system in the car. It could be a minor problem such as a malfunction rectifier unit, blown fuse or cabling short circuit.
Your battery needs to be charged if the battery light illuminates, signaling a low battery. You can reset the light by disconnecting the negative terminal of the battery for a short while if the battery or charging system of the automobile is working properly.
There are many reasons why the car battery light might come on, but generally, the reasons are: An old car battery. Car battery connections that are corroded. Car battery cables that are misconnected.
If your battery warning light comes on whilst you`re driving, it means that your battery is no longer being charged by the alternator and is running only on its own charge. That means that your car is only running on battery power that will eventually run out, bringing your car to a halt.
The new battery does not have to be configured for the most current car models. Banner conclusion: No registration required; a check of the electrical functions after changing the battery is recommended.
This indicates that the alternator is not working properly. What is this? The most common cause of this problem is an alternator failure. Alternators are responsible for charging batteries in cars and other vehicles, and when they fail they can cause all sorts of problems with your vehicle`s electrical system.
Steps to Reset an Engine Light

Locate the negative terminal on your car battery. It will have a black cap and a negative (–) symbol. Using a wrench, loosen the nut on the negative battery terminal and pull the negative connector from the battery. Keep it disconnected for 30 to 60 seconds.

Like desktop computers and most other electronics, disconnecting the battery cable for a short period will not fully reset your ECU due to the residual power remaining in the circuits.
There are many reasons your car`s battery might be dead, and one of them happens to be a broken voltage regulator. This is because when this part burns out, the battery will no longer charge, meaning it will eventually die.
If your alternator voltage regulator is working correctly, your battery`s voltage output should cap around 14.5V. If the reading is above 14.5V, you likely have a faulty voltage regulator. If the reading is below 13.8V, your battery is weak and will probably need a replacement.
If your Ford Explorer battery warning light comes on while driving, be bold to turn off your accessories, so the battery doesn`t jettison additional. The warning light usually means that the alternator isn`t working accurately meaning you are operating solely on battery power.
Can I Keep Driving My Car if the Battery Light Is On? Yes, you can, for a short time. The light indicates that the alternator isn`t charging the battery, which means your car`s electrical system isn`t getting the needed power.
There are many reasons why your battery light could turn on. It could indicate a bad battery or dead battery, a charging problem, a faulty alternator, a wiring issue, and so on. And while driving with the vehicle`s battery light on is possible, it`s not recommended.
The red battery light basically means that there is an issue with your alternator, your battery, or some other part of the charging system which could be as minor as cabling or as major as a computer malfunction.
A. It depends on the car`s age and type of ECU used. On some older cars, disconnecting the battery will reset the system but in most new cars it does nothing, except potentially reset the clock and radio station presets.
If you were to replace an aged battery at the end of its service life with a brand new battery without updating the BMS, your new battery`s performance and service life will be compromised. This is why a new car battery should be coded to your vehicle.
In general, you will need to drive between 50-100 miles after you clear your car`s computer. Hopefully, this will get rid of the check engine light once and for all.
You can attempt to bypass Limp mode by restarting the vehicle after a short wait or by removing one of the battery terminals to reset the electronic systems.
At least 5 minutes or quicker if you disconnect both terminals and hold them together. Make sure that nothing touches the battery terminals.
Turn the air conditioning on and allow the engine to idle for at least one minute. Release the parking brake. With your foot on the brake pedal and the A/C still on, put the vehicle in “D” (Drive) and allow the engine to idle for at least one minute. Drive the vehicle to complete the relearning process.

Relevant Questions and Answers :

the most relevant questions and answers related to your specific issue

in my car battery warning light appearing while driving.so I have replaced both battery and alternater still light is on
ANSWER : As you may yourself have seen, there are many reports of this fault with the Civic, that is a battery or alternator is replaced only to have the warning light fail to extinguish despite checking every conceivable electrical possibility. Your only recourse is to have a certified mechanic go through that exercise with your car and that involves first attempting to "re-set" the light. If the warning light returns, the alternator output has to be carefully measured both loaded and unloaded. All terminal connections have to be verified including all grounds. Fuses have to be checked for integrity (continuity) and the possibility of shorts, in for example dash wiring, has to be checked. To request this repair, simply request an electrical components diagnostic and the responding certified mechanic will seek a resolution to this.

Car battery light is on replaced alternator battery and starter and battery light is still on.
ANSWER : You may have a failing voltage regulator that could be allowing the alternator to supply too much or too little amperage to the battery resulting in the battery never maintaining a consistent charge as it is designed to. The voltage regulator is a unit that regulates the charging of the battery by the alternator. When the voltage regulator is not working properly, this may result in the alternator allowing too much power to be delivered to the battery resulting in damaging wires and prematurely sometimes destroying the battery. A common sign of this is usually the acid inside the battery boiling causing the battery to swell. You may also smell a bit of smoke due to things potentially getting too hot. In other cases it may result in the alternator not supplying enough power to the battery, resulting in undercharging the battery or not charging it at all. I would recommend having an expert from YourMechanic come to your location to diagnose your vehicle’s charging system.

I have Chrysler 300c. Battery light came on, changed battery and alternator but power still getting drained and battery light still comes on.
ANSWER : Hi, thanks for writing in. This may be a sign of a failing starter relay. The starter relay is a small unit near the starter that directs power to the starter from the battery. When this fails, it may cause a clicking sound and will not allow the starter to engage the flywheel when you turn the key. I would suggest having a professional from YourMechanic come to your home to diagnose your starting issue to determine the solution to get you back on the road.

Car won’t start. The check engine light, battery light, and oil change light are coming on. I tried jumping the car and nothing happened. Why won’t my car start?
ANSWER : Hi and thanks for contacting Your Mechanic. If sometimes your vehicle will start with the new alternator and sometimes it won’t, then there is a loose connection in your charging system. Check all of the wires to the alternator and to the battery. Make sure that the battery cables are clean and tight. Make sure that the wires to the starter are clean and tight. A loose ground to the ignition system will cause the vehicle to not crank over. Check all of the ground wires from the battery to the starter. Make sure that they are clean and tight. If you need further assistance troubleshooting your no start situation, then seek out a technician, such as one from Your Mechanic, that can assist you.

is the ecm the problem if battery light is on and the alternator isn’t bad
ANSWER : This is likely a sign of a failing voltage regulator. This is a unit that regulates the charging of the battery by the alternator. In your case, it sounds like the voltage output from the alternator may be much too high resulting in overcharging the battery and burning up wires in the process. I would recommend having an expert from YourMechanic come to your location to diagnose and properly test your vehicle’s charging system.

2005 Chrysler 300C changed battery and alternator. Car started, ran, and then battery light came on. Shut car off and wouldn’t start.
ANSWER : Hi. There is a couple of things that could be wrong here. The battery or alternator that was just installed could be defective. Theses parts need to be tested for proper operation. There also could be a fuse, fusible link, or wiring for the battery or charging system that is blown or broken causing the battery light to come on.

The codes that you have will cause the car to shut down, run rough, or not start at all. The crankshaft sensor and camshaft sensor should be replaced. I suggest having a certified technician from YourMechanic come diagnose the charging system and check engine codes to help you proceed with correct repairs.

Battery light stays on and overnight battery drain. 2006 Land Rover LR3
ANSWER : Hello – this problem can be diagnosed by connecting an ammeter to the positive (red) battery cable, observe the current drain (likely less than 1 amp), then, one at a time, remove each fuse, check to see if the current drain has dropped to near 0, then reinsert the fuse. This process should identify the faulty circuit in most cases. The specific components on that circuit can then be checked for current drain problems. A professional mechanic, like YourMechanic, can come to your location, and perform this procedure for you, and identify, replace or repair the failing component.

Battery light stays on and overnight battery drain. 2006 Land Rover LR3
ANSWER : Hi there – yes, something is going on here that’s draining your battery. Perhaps the pressure of the engine wash dislodged wiring which has shorted, or there was a chemical reaction to the cleaning solution that caused electrical damage in the alternator or voltage regulator. These componnents can be checked off of the vehicle. Vehicle wiring can be diagnosed by connecting an ammeter to the positive (red) battery cable, observe the current drain (likely less than 1 amp), then, one at a time, remove each fuse, check to see if the current drain has dropped to near 0, then reinsert the fuse. This process should identify the faulty circuit in most cases. The specific components on that circuit can then be checked for current drain problems. A professional mechanic, like YourMechanic, can come to your location, and perform this procedure for you, and replace/repair the failing component.