Why is the battery light on but the alternator is charging?

1 Check for Corrosion. In some car models, the fumes from the regular functions lead to corrosion to collect on the battery terminals. 2 Clean the Car Battery Terminals. If you notice some corrosion or grime around the battery terminals, it might be the reason why the car battery light is still on. 3 Tighten the Battery Clamps. …

What are the symptoms of a bad alternator in a Chevy Silverado?

Outside of the battery warning light, a dead battery is the most common symptom of a bad alternator. As the alternator can no longer supply your Silverado with an adequate power supply, it will begin to feed off of the reserve in the battery.

How many volts does an alternator need to charge?

Let’s go ahead and leave the air conditioner off, as well as the headlights and any other accessories. With the engine just fired up, you should get over 14.2 volts. If you got 14.2 or more volts, the alternator is charging fine. If it’s still showing in the 12’s, it’s time to replace the alternator.

How can I tell if my alternator or battery is OK?

As with most electrical issues, if you know the battery or alternator is OK (because you had it tested), then diagnosis comes down to tracing and testing for continuity from one portion of the circuit (s) involved to the next.

Can a battery be charged if the alternator is not working?

The alternator is definitely charging the battery and does not drain overnight but the battery light continues to stay on. Before spending money to test the fusible links, please advise If the alternator will still charge the battery with a faulty or blown out fusible link? Thanks. helpful? It will charge if one link is still working.

Why does the battery light stay on when you start the car?

In case the battery light stays on when you start the car, do not worry. It is usual for the light to power on when you turn the ignition to your vehicle. Usually, the light turns off after some time, but if it stays on even when you are driving, then pay attention.

Why does my alternator light keep going off?

Even though the alternator is new, doesn’t mean it is a good part. We have seen many times where people get burned due to faulty new parts. Then if this light is going off when you raise the RPM then that means by spinning the alternator faster to increase the output puts the voltage over the minimum spec to turn the light off.

Can a generator be replaced with an alternator?

It appears your system has an alternator which means it is a PCM controller voltage regulator. Generators are the ones with internal voltage regulators and are replaced with the generator. Take a look at the attachments but Navigators with this issue usually have a failed regulator in the PCM. Let me know if you have questions.

What causes a battery warning light on the dashboard?

See how you can fix the battery warning light on dashboard with this five problem that you can look at. While the battery light might seem like there is a battery problem, but in fact there could be other numerous issue causing the battery light to activate. To see what is really wrong with the car see this video for things you can check.

What should I do if my Battery Light is intermittent?

You could take your alternator down to most parts shops and get it checked, but it may not show an intermittent charging issue. You can also check all of your connections and grounds to ensure they are tight, clean, and making good contact.

Why is the battery on my Mitsubishi Galant not working?

After several weeks of driving with this condition, the car refused to start. The battery was completely drained. Mechanic tested the new battery and found it to be bad. Replaced with new second new battery. Symptoms disappeared totally for about 2 weeks. Now back to same symptoms of having the battery light come on at start up.

How can I tell if I have an alternator problem?

To differentiate an alternator problem from the battery, you will need to use a voltmeter to check for voltage. First, turn off the engine and check the battery voltage. A fully charged battery should have a reading of 12.65 volts. Next, turn on the engine and recheck the voltage. You should have a reading of 13.5 to 14.5 volts.

How can you tell if your car charger is in trouble?

Usually, the first sign that your charging system is in trouble is a “battery,” “ALT,” or “CHARGE” warning light illuminating on your instrument panel while driving. It means that for some reason, the alternator has stopped charging the battery and your car is running on battery power.

What does the charge indicator light mean on a car?

Indicator Light On Usually, the first sign that your charging system is in trouble is a “battery,” “ALT,” or “CHARGE” warning light illuminating on your instrument panel while driving. It means that the alternator voltage output is below 12 volts, or over its limit or has stopped charging the battery and your car is running on battery power.

What does it mean when your alternator stops charging the battery?

Indicator Light On. Usually, the first sign that your charging system is in trouble is a “battery,” “ALT,” or “CHARGE” warning light illuminating on your instrument panel while driving. It means that for some reason, the alternator has stopped charging the battery and your car is running on battery power.

What happens when the check charging system light comes on?

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.

Where can I go to test my alternator and charging system?

If any testing or replacement of your alternator or charging system becomes too difficult of a job, consider visiting one of our Preferred Repair Shops in your area can help you diagnose and repair any faults in the charging system.

What should I do if my alternator is not working?

The first course of action is to check the wiring carefully that runs between the alternator’s main power wire and the battery. A worn, loose, or damaged connector can cause a massive voltage drop. If everything appears fine, the alternator should be removed and bench tested, which can be done for free at AutoZone.

How do I know if my battery or alternator is bad?

Signs of a bad alternator. If the above steps reveal that the battery is working, it’s time to take a closer look at the alternator. There are certain signs of a bad alternator to look for: While running the car, note the brightness of the interior lights. If the dashboard gradually dims, the alternator is likely at fault.

What happens if my alternator overcharges?

An overcharging alternator will cause the voltmeter on the vehicle’s dash to read an overly high voltage that may or may not vary with engine speed. Normal readings should be high upon start-up, then settle into the normal range. An overcharging alternator, however, will cause the meter to remain in the high position after initial start-up.

How do you check bad alternater?

A simple test to check the working of the alternator is by running your car; and then unplugging the positive connection of the battery. If the car stops, then you most likely have a problem with the alternator. Another simple test is to check your interior lights.

What causes an alternator to over charge?

What causes an Alternator to Overcharge? Step One. Battery – Alternators that overcharge will typically produce excess voltage to the battery, making the battery case swell up, become very hot and lose its electrolyte through boiling. Step Two. Step Three. Step Four. Step Five.

Why does my alternator light go off when I raise the RPM?

Then if this light is going off when you raise the RPM then that means by spinning the alternator faster to increase the output puts the voltage over the minimum spec to turn the light off. If all this checks out then I suspect you have a wiring issue.

What causes an alternator to go over base voltage?

If you are getting more than 2 volts above base voltage, most likely your alternator is over-charging the battery or the battery is faulty. Other potential problems are a faulty voltage regulator or a problem in the charging system wiring.

Where is the charging light on an old car?

Alot of time on this old cars the regulator goes bad.The charging light comes off the regulator. It’s the red&green wire. The regulator is located on thr driver side mounted on the inside of the radiator core support.It is easy to change out. Start the car, take off the positive battery cable.

Can a bad alternator cause check engine light to flash?

No, the check engine light flashing and the misfire probably does not mean the alternator. It most likely refers to a engine sensor malfunctioning. What you will have to do is have the engine trouble codes retrieved to find out what that check engine light is referring to.

Where does the warning light wire go on an alternator?

If the alternator is fitted with an internal regulator, the wire you want connects directly to a terminal on the back of the unit marked WL or IND. If the alternator has an external regulator, the warning light wire attaches to it in the same way as a dynamo.

Why is your new alternator not charging your battery?

The most common reason for an alternator not charging a battery is because of a bad alternator or battery . You can easily test the voltage by connecting a voltmeter to your battery while the engine is off.

Why does an alternator overcharge?

Typically, one of two problems cause overcharging alternators: poor battery condition and failed regulators. When a battery is already getting old and worn down, the alternator may run extra hard to increase its charge. However, overcharging of any type still triggers battery damage,…

How do check alternator?

Why does my car battery light keep coming on?

Replaced alternator and battery. When you start car battery light comes on then goes off, comes on again five minutes later, goes off again. If you drive more than twenty or thirty minutes battery light comes on and stays on.

When does the battery warning light come on?

When you start car battery light comes on then goes off, comes on again five minutes later, goes off again. If you drive more than twenty or thirty minutes battery light comes on and stays on. After another few minutes all warnings lights flash and all gauges freeze, then power steering goes out and car dies completely.

What happens when you change the battery in a car?

A relatively common “side-effect” of replacing a battery and/or alternator in a car is to have the voltage (battery) warning light come on. This is especially true in late-model vehicles with their more sophisticated internal diagnostic systems. There are usually two things…

Is the battery light on but battery charging OK?

Going nuts – Battery light on but battery charging OK. The battery light is on but the voltmeter says 13.5 to 14.5 volts depending on the engine revs. When engine is off the volts drop to about 12.

How to troubleshoot intermittent Battery Light issue in..?

The easiest what to check for this is to have a helper in the driver’s seat, engine running, then you go through and move wires associated with the charging system around a little bit and see if you can get the light to come on. Like I said, a long shot, but about the only other thing you could check.

What causes the charge indicator light to come on?

You may notice: your ALT or CHARGE indicator light comes on, your engine is hard to start and cranks slowly, or doesn’t crank, your battery demands lots of water, your alternator makes noises, or your headlights suddenly go dim. These and other problems may be caused by a fault in the charging system.

What’s the volt meter on my GM Truck?

The battery light is still intermittent. The volt meter in the truck reads 14. When I hook up the multimeter it reads 13.8 with no accessories running. When I turn on everything, AC on max, Stereo and Lights on bright, it drops down to 13.1 but never drops lower.

What to do if your car battery light is not working?

Get the alternator or wiring fixed, and properly recharge the battery at the same time. The folks at AutoZone can always help with battery and charging system issues, both on the car, and with the parts off the car.

Where is the volt meter on an alternator?

To diagnose the problem, put the positive wire of your volt meter on the alternator output terminal and the negative wire of your volt meter on the battery plus terminal. Put some load on the battery, such as lights or something, rev the engine, and see how much voltage is getting dropped between the alternator output and the battery terminal.

Why does my alternator light get brighter when I Rev the engine?

This voltage drop causes the light to light, and also results in the battery charging poorly if at all. Usually when this is the case, the light will be very dim at hiatal and will get brighter as you rev the engine.

Why does my car battery voltage meter fluctuate?

A simple problem of loose wires and connections can cause your battery voltage to fluctuate. You may think it is flat, charge it and afterwards voltage can go as high as 15V or 16V. Why does my car battery voltage drop?

What does it mean when your car battery light is on?

The battery light or charging warning light, available on the dashboard of your car, indicates malfunctioning or poor charging of the battery. This light illuminates whenever the charging system does not charge the battery with a voltage above approximately 12.5 volts.

Can a car battery be drained by an alternator?

While you might initially think that any problems with electrical things like lights or radio not working are directly related to the battery, the alternator is actually where most of the power in your vehicle comes from. Consider that if you were to leave the lights of your car on overnight by the next day your battery might be drained completely.

What causes the battery light to go out?

Click to expand… Many charging systems put the alternator energizer wire through the light bulb. When the alternator starts charging positive voltage is equal on both sides of the bulb filament and the light goes out.

Why would a good alternator not charge a battery?

The alternator is powered by several different wiring mechanisms. If a wire is not attached properly, becomes detached or is inadvertently cut, the alternator will not have any power. If the alternator is not getting any power, it cannot turn the pulley and belt mechanism that charges the battery, and the battery will not charge.

Will a car with a bad alternator start with a new battery?

A bad alternator can prevent a car from starting because it did not charge the battery when the car was running. However, even if you have a dead battery because of the alternator, you can still jump-start the car using the following method.

Why does your battery light keep coming on?

There are a few different reasons why your vehicle’s battery light came on. It could be a problem with your alternator, which recharges your battery while your engine is running. It could also be a wiring issue such as a damaged or disconnected wire affecting your battery.

When to check the voltage of the alternator?

When investigating a flat battery or other potential issue you should always check the voltage with the engine running to make sure the alternator output is charging the battery sufficiently otherwise your only guessing the battery is at fault – as you found out the fault was elsewhere.

Can you change the battery light on a Ford Focus?

Had mine change and totally different car, runs quicker, no turbo lag, start quicker and much smoother, have you got obd2 and forscan will bring up code or try the in car code check ot sure how to doit but google will tell you i imagine i take that on board when checking glad you did not have a fire not nice

Why does the battery warning light come on after replacing the alternator?

What should the resistance be for an alternator?

If all this checks out then I suspect you have a wiring issue. I would perform either a voltage drop or resistance measurement of each of the wires from the PCM to the alternator. Also, through the fusible link from the battery to the alternator. You should have less then a half ohm of resistance.

What’s the problem with the battery charging fault?

Problem – My dash is intermittently flashing Battery Charging Fault, ABS light, and STOP. Car sat for a week in an airport car park while on holiday, when I returned the orange service light was illuminated. Few days later this changed to a beeping alarm with BATTERY CHARGING FAULT and STOP light.

Why is my Renault battery charging fault still there?

Few days later this changed to a beeping alarm with BATTERY CHARGING FAULT and STOP light. The mechanic changed the battery as it was overcharging. Fault was still there so he changed the alternator. Fault was still there with the new alternator. My old alternator got sent for testing and no fault found so it got refitted.

What are the signs of a failing alternator?

5 Signs Of A Failing And Faulty Alternator 1: The Warning Light 2: Unusual noises 3: Failing headlights or electronics 4: Your car has difficulty starting, or stalls 5: Your battery is dead

Why is the battery light still on after a battery change?

Replaced battery (under warranty, appeared to have one cell bad) but still doing it. Drove to the parts store, pulled the alternator out in the parking lot (could do it in about 5 minutes by now) and brought it in and tested it while hot, it failed.

Going nuts – Battery light on but battery charging OK. The battery light is on but the voltmeter says 13.5 to 14.5 volts depending on the engine revs. When engine is off the volts drop to about 12.

Why is the battery light still on after a new alternator?

So, now truck has new alternator and battery BUT battery light is still staying on. I had them check both and they said, new battery and alt showing good. I know all of the connections are tight and I checked the fuses inside the truck and all are good.

What causes the battery light to come on but not charge the battery?

I was told a blown fusible link will trigger the battery light to come on and will not charge the battery. Based on what you are saying, if one of the fusible links is faulty it will cause the battery light to come on but will continue to charge the battery.

What to do if your Ford dashboard light comes on?

Make an appointment with your local dealer as soon as possible. Charging System: If you’re driving while this light comes on, switch off all unnecessary electrical equipment that you may have running and get your vehicle checked by an authorized mechanic immediately.

What do the warning lights on a Ford car mean?

Not all warning lights indicate a massive, immediate problem with your car. Each Ford instrument cluster is loaded with warning lights and notifications, and not all are bad. Knowing what your dashboard is trying to tell you may prevent that panic attack the next time a warning light flips on.

What causes a car charger light to come on?

Drive belt troubles – A failed drive belt prohibits the alternator from doing its job and can cause the warning light to come on. Have your mechanic check the condition of your vehicle’s drive belt.

What should the voltage be on a bat alternator?

Measure the voltage across the battery and the big bat alternator terminal to alternator case. There are two things that you are looking for. The charging voltage should be between 13.9v to 14.4v. Also the voltage at the battery and the voltage at the alternator should be within 0.5v of each other.

What to look for in an alternator Charger?

Turn on all the loads (blower on high, headlights on, rear defrost on, and so forth). Measure the voltage across the battery and the big bat alternator terminal to alternator case. There are two things that you are looking for.

What to do if your alternator has low voltage?

Put the black multimeter probe on the negative battery terminal (if possible dig it into the battery post, not the terminal). Put the red probe on the alternator case. Your looking for the voltage to be below about 0.5v. If the voltage is higher than that examine all the negative cabling for problems. Preform the same test with the positive side.

Why is the battery light on but the alternator is charging?