Charging system warning light.

when at idle the head lights and dash lights are very dim and battery light is on when u rev the car up the lights get way brighter and battery light goes off what could this be?

My car has 223000 miles.
My car has an automatic transmission.

Experienced mechanics share their insights in answering this question :
Hi There,
As you know, the alternator charges your battery and relies on engine RPM’s to generate more voltage to the system as needed such as when accessories or lights are turned on, which draw down the electrical system. As this happens, the alternator is required to work harder to generate more voltage to power these accessories. The higher your engine RPM’s turn, the more voltage is produced, thus making the lights brighter. If they dim to a certain point, this suggests that the voltage regulator may not be allowing the alternator to produce the proper voltage to the electrical system at lower RPM’s. I would recommend having an expert from YourMechanic come to your location to diagnose and inspect your electrical system.

How to Identify and Fix Common car Problems ?

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

Charging System Warning Indication/Warning Light

If the warning light illuminates while driving, it indicates a malfunction of the alternator or of the charging system. Drive to the side of the road and park off the right-of-way. Consult an Authorized Mazda Dealer.

If this warning lamp lights up while the engine is running, it means that there is a problem in the charging system, usually that the battery has gone bad or the alternator has stopped working. Sometimes if your car or truck won`t start, you have a bad battery, one that can`t hold a charge.
If the Brake warning light comes on and stays on, it may indicate that your parking brake is still engaged. It could also mean that your brake fluid level is low and needs to be filled. This should be addressed immediately. Most newer Mazda vehicles are equipped with a Tire Pressure Monitoring System.
What`s happening when the battery/check charging system light comes on? Whenever this light goes on, it means that the vehicle is running solely on battery power. If the problem continues and your charging system fails, the battery won`t be able to recharge and it will soon run down, leaving you with a dead battery.
While you can technically still drive with a bad alternator, it is not advised. This is especially true in newer vehicle models. This is because there is more electricity involved compared to an older model.
Faulty Switch: One common reason for the Parking Brake light to stay on is a failing or failed switch. This can be checked easily by moving the handle to and fro after it is down. If the light turns off (or turns off and then back on), the switch is the most likely culprit and will need to be replaced.
The most common cause your brake lights stay on is because of a faulty brake light switch or sensor. It can also be caused by a faulty brake pedal or a malfunction in the electrical system. If you recently replaced the rear light bulbs when it occurred, you may have installed the wrong light bulbs.
If one or more of your brake lights aren`t working properly, it could mean one of three things: The brake light system fuse is blown, the brake light bulbs are burned out or the brake light wiring switch is broken. All these issues are easy to troubleshoot.
Another common problem that can cause the charging system to fail is a broken alternator belt or one that is worn so bad it slips badly. If the alternator works properly but the belt doesn`t spin it fast enough, the voltage output can drop and cause the system to act as though the alternator doesn`t work.
How long can I drive my car with the battery light on? If your battery light stays on while you drive, you`ll have roughly 30-60 minutes to drive with your battery lights on before your car may start stalling.
A blown fuse could be a cause of the battery light to come on. Excessive voltage in the electrical system can blow the fuse and prevent charging of the battery. A electrical technician can replace the fuse quickly and it an inexpensive fix.
The alternator belt is the connection that interfaces the crankshaft and alternator together. If your car`s alternator belt isn`t working properly, your car battery won`t get the charge it needs for your vehicle`s electrical parts. With that, your car battery light will frequently be on to indicate such an issue.
#1 – Dead Battery

A battery that is drained or can`t hold a proper charge is one of the most widespread problems across all automobiles.

It is unsafe to drive with your car battery light on. Issues that activate your car battery light, like a defective battery or faulty alternator, can cause your car to lose power. In these instances, your car won`t operate as it normally would.
Insert the key (or key fob) in the ignition. Move the key to position 2, but don`t start the ignition. Open the driver`s door and wait for approximately 10 seconds. After completing the above three steps, the brake pad lights should reset!
While you technically can drive with the brake system warning light on, you should make a point to remedy the situation as quickly as possible. Brakes are the most important safety feature on your vehicle, so you should not drive if your brakes are not working properly.
The brake light switch sensor lets the ABS module in your car know when you`ve applied the brakes and indicates that it`s time to start the ABS hydraulic pump. That`s why if your ABS warning light comes on, there`s a chance that your faulty brake light switch is the culprit.
Like all fuses, the brake light system fuse can be found in the power distribution center, which is under the dashboard or tucked away underneath the hood.
The stop lamp fuse is in the left kick panel inside the vehicle. It is a 15amp fuse that powers the stop light switch on the brake pedal.
The most common reasons your brake light is on: The Parking Brake is engaged. Brake Fluid is low or leaking. Worn brake pads.
Car Battery Gets Hot When Charging

If your car battery gets hot while charging, this means that overcharging is causing excess electrical charge to be radiated as heat.

The check engine light is usually the most serious and feared warning because of the kind of damage it can signal. This warning often indicates the potential for serious engine damage. When ignored, your vehicle could suffer from a blown head gasket or a seized engine.
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.

Relevant Questions and Answers :

the most relevant questions and answers related to your specific issue

Car shut down and will not start. Warning lights are on – 2006 Toyota Highlander
ANSWER : Hello. From what you describe, it would appear that your vehicle is having some sort of electrical issues. The "Generator Inverter Performance" warning comes on when the computer detects an issue with the vehicle’s electrical generator inverter. The generator inverter is the component that converts the high current electricity from the vehicle’s hybrid battery into a lower power form of electricity that is useable by the vehicle’s various systems.

The inverter is located in the engine bay, as the silver box on top of the engine. Unfortunately, the inverter is a critical component to the functionality of the hybrid system, and therefore to the operation of the vehicle, and, as a result, needs to be repaired or replaced before the vehicle will run again.

The VSC system warning light comes on when the computer detects an issue with the vehicle’s stability control system. This is usually due to a fault with the wheel speed sensors or the ABS module, though electrical issues can sometimes effect this system as well and cause it to behave erratically. I would start by taking care of the generator inverter issue and going from there.

I recommend having a certified mechanic, such as one from YourMechanic, perform an inspection to determine why the warning lights are on and suggest any needed repairs.

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No dash lights, back right tail light is out, no parking lights. Brake lights work though as does head lights.
ANSWER : Hi there. In many cases, when you have electrical problems like you’re describing, it’s caused by multiple electrical component failure. It’s likely that a few electrical relays are not working; especially if you have systems that utilize the same components (such as your brake light and tail lights). I would recommend having a professional mobile mechanic come to your location to complete an electrical problems inspection first, so they can pinpoint what is damaged and recommend the right repairs.

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My Accord gives out a "Charging system failure" warning. I drove home about 15 miles and then parked my car. After about 3 hours,
ANSWER : Hi there. On a new Honda Accord, the Charging System Failure warning light typically indicates a problem with the battery, alternator or other component inside the charging system of your vehicle. However, with less than 10,000 miles, this is most likely an electrical glitch or stored error code that was triggered. Since your car is "new", I would recommend contacting your Honda dealership first, to tell them about this warning light and ask them how they wish to handle this issue; as it should be covered under warranty. If they can’t help you, please set up a warning light inspection, and one of our mobile mechanics can come to your location and determine why this light came on.

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Abs light, emergency brake light, steering wheel assist light, engine light, EPC light, traction control light
ANSWER : Hello, thank you for writing in. The vehicle does utilize a lot of the same sensors for these systems. Are there any other codes that are coming up when this code appears? If so you will want to take these into consideration when processing the repair and making a diagnosis. The module may be bad, and replacing it should fix the problem. The lights should turn off once the main computer recognizes the new module and the sensors sync up. If you believe the sensors need to be cleaned you may do so. Do as minimal as possible to make sure you are not damaging the sensor or disrupting the wiring inside. A bad connection would make the lights stay on. With so many lights that are effected by the module being illuminated, the module is likely bad or does not have a connection. Check the connection first and then resort to replacing the unit. For more help with these electrical tests, contact our service department.

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check break system and indicators of side brake, doors open,and traction system and full light warning in dash board
ANSWER : Hi there, thanks for writing in.

It sounds like you are having a serious electrical malfunction, which is very hard to diagnose without being able to look at the car first hand. The first step to diagnosing your electrical issue would be to scan all the relevant control modules in the vehicle, to see if there are any faults relating to any of these issues. It sounds like somebody at the dealer has been trying to fix this problem, so it may be a more involved one. I have personally seen failed control modules cause things like this, but that is no guarantee that it’s the problem in your case. It would be best to have a qualified independent technician, such as one from YourMechanic, look at your car to diagnose your electrical problem.

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on a 1970 Lincoln mark iii Interior lights wont turn on and warning lights are very dim and doorlock button makes buzzer go on
ANSWER : Hi there. Although the electrical systems on older vehicles tend to be much simpler in design, in many cases, issues like you’ve described can be very tricky to trace. It could possibly be something as simple as an expose wire creating an electrical short or a faulty relay that is not completing an electrical circuit. I wish we can help you further, but the best advice I can offer is to have one of our mobile mechanics come to your location and complete an electrical problems inspection.

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What is the difference between engine oil warning light and another warning light just like that but with waves under the sign? 1996 Mitsubishi Galant
ANSWER : Hello- the warning light you mention is a " low coolant" indicator. Once the engine is cool – check your coolant reservoir and/or cooling system for proper fluid level. Since you seem to have lost fluid, I would recommend an inspection of the cooling system by a mobile, professional mechanic, such as one from YourMechanic, who will come to your location, diagnose this problem, give you an accurate assessment of damage and cost estimate for repairs.

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2012 equinox reduced power light engine light and traction light came on. Lost a lot of power got home and all light except engine
ANSWER : Your car has what is called a "safe mode" that will be engaged by the computer when it detects that something critical has gone wrong related to any of the major components in your engine chassis or power train. This may be related to a number of things, most of which should have been registered in the computer when the check engine light came on. I recommend having an expert from YourMechanic come to your location to inspect your check engine light and diagnose any codes registered by your vehicle’s computer.

Read Full Q/A … : Charging system warning light.