Battery good, alternator good, brand new alternator cable, still not charging.
I need help finding out what could be wrong with my charging system. One day my 2003 Expedition didn't start, got a jump start and took it to auto zone to check. Battery voltage was too low to test, so I took battery out and left it out overnight, next morning picked it up, they said battery was good and held charge. Put battery back in and took it for testing, their test said the voltage regulator was bad, so bought a new alternator, installed it, same thing, not charging. Took old alternator back so they could run a bench test, old alternator came back good. So I just recently replaced t
Experienced mechanics share their insights in answering this question :
Hi There,
The first diagnosis of the bad voltage regulator is likely the cause of your charging system not properly charging the battery. 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. 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. In some cases when a battery is too weak or damaged, it may no longer hold a charge for any length of time, in which case the alternator may be doing its job, but the battery is just simply too weak to hold a charge. In either case, I would recommend having an expert from YourMechanic come to your location to diagnose your vehicle’s charging system.
The first diagnosis of the bad voltage regulator is likely the cause of your charging system not properly charging the battery. 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. 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. In some cases when a battery is too weak or damaged, it may no longer hold a charge for any length of time, in which case the alternator may be doing its job, but the battery is just simply too weak to hold a charge. In either case, 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 ?
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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.
Charging problems can be caused by electrical faults in the alternator or voltage regulator, poor wiring connections at the battery or alternator, or a slipping or broken drive belt. Since most late-model import alternators are internally regulated, a failure of the regulator means the alternator must also be replaced.
Poor ground connections are an often-overlooked cause of low charging output and alternator failure.
If the alternator`s fuse or fusible link is blown, the alternator will not be able to charge the battery. The battery then doesn`t store enough power for starting the car or keeping it running.
What may drain a car battery when it`s off are things such as interior lights, door lights, or even bad relays. While your engine runs, the alternator recharges the battery — which is why you typically don`t have to worry about the battery dying while you`re blasting the radio on your drive to work!
Symptoms of An Electrical Ground Fault
However, a few common symptoms of electrical ground faults are: Strobing lines on your TV or desktop computer monitor. Humming or buzzing in your home stereo or TV audio system. Unexpected shocks when you touch metal appliances, trim, or pipes.
The most common and possible reasons why your car battery won`t hold a charge include an old battery, loose or corroded terminals, an improperly charged battery, an overcharged battery, a charger issue, weather conditions, taking very short trips, leaving the engine off for an extended period of time, or leaving the …
While the size of your fuse depends on the amperage of your alternator, you should generally select a fuse that can handle more amperage than your alternator is able to output. For example, if your alternator outputs 200 amps, you should choose a fuse that`s no less than 200 amps.
The light should go out when the problem is repaired. It may not go out immediately though. You need to have your alternator checked.
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. Q: I have a headlight that is dim.
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.
Relevant Questions and Answers :
the most relevant questions and answers related to your specific issue
Battery good, alternator good, brand new alternator cable, still not charging.
ANSWER : Hi There,
The first diagnosis of the bad voltage regulator is likely the cause of your charging system not properly charging the battery. 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. 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. In some cases when a battery is too weak or damaged, it may no longer hold a charge for any length of time, in which case the alternator may be doing its job, but the battery is just simply too weak to hold a charge. In either case, I would recommend having an expert from YourMechanic come to your location to diagnose your vehicle’s charging system.
The first diagnosis of the bad voltage regulator is likely the cause of your charging system not properly charging the battery. 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. 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. In some cases when a battery is too weak or damaged, it may no longer hold a charge for any length of time, in which case the alternator may be doing its job, but the battery is just simply too weak to hold a charge. In either case, I would recommend having an expert from YourMechanic come to your location to diagnose your vehicle’s charging system.
Put a brand new alternator in it and new battery and it still does not want to charge the battery is this
ANSWER : Inspect fuse number 11 and 30 in the fuse box. Check the grey fuse link near the starter. If both of these are good then check fuse 19. In fact, its best to check all the fuses for any blown ones. Have the computers scanned to see if the computer has codes for the charging system. The alternator charging is controlled by the computer, and I have found that sometimes aftermarket alternators do not fix the problem. Some vehicles have more factory options for alternators than what the aftermarket offers. If the fuses do not help then you may have to replace the alternator with a dealer supplied one. On some of these vehicles they also had problems with the instrument cluster and connections to the cluster, which could be playing a part. If you cannot find the problem, then have a technician, such as one from YourMechanic, come and check the system for you.
my battery kept draining until i bought a new alternator and battery. i have tightened the belt on the alternator but it still die
ANSWER : Hi there. The best way to diagnose why a battery would constantly drain is to review it’s job and how it is recharged. The battery is responsible for powering all electrical systems until the vehicle is started. At this point, the alternator takes over and also continually charges the battery while the vehicle is in use. A battery will drain when one of two things occurs. First, a battery will drain if it is constantly in use; supplying power to an electrical component even if the key is not in the ignition. Second, the battery will eventually die if the battery is not being charged frequently. However, since this is happening every two days, my initial thought would be that some electrical component on your 86 Olds is continuing to draw power from the battery. This is known as a parasitic drain. The best way to determine the source of this battery issue is to have one of our professional mobile mechanics come to your location and complete a battery will not hold a charge inspection.
My service charging system battery light is on after replacing my alternator with a brand new one. It is not charging my battery.
ANSWER : Hello, thank you for writing in. Several things may be going on. The installation of the new alternator needs to be verified, focusing on the electrical connections and the drive belt. Make sure the connections are clean, dry, and tight. Make sure the drive belt is routed properly and is tight on the alternator pulley (as it is what powers the alternator). If the installation was fine, you will want to make sure the alternator was not faulty from the factory. It is not common, but these issues have been known to happen. Most automotive parts stores can test the alternator off of the vehicle. If you would like more help with testing, contact our service department to schedule an appointment.
We have a new battery, new alternator, new coil pk, new master fuse and the car still won’t hold power.
ANSWER : Hi there. The only thing that I could think possible is causing your problem is that something may not have been correctly installed while your son was completing this maintenance. However, if your engine was difficult to start before this service, it’s possible there are different components that are damaged that simply didn’t resolve the issue. The only way of knowing what is going on with your Trailblazer would be to have one of our mobile mechanics in your area come to your location and complete a car is hard to start inspection.
battery alternator light still on even though i have a new battery and alternator
ANSWER : If you check the big black cable from the alternator to the battery and there is no voltage with the engine off, then that cable needs to be replaced. On the transmission bell housing, that cable has a 175 amp fuse in the harness that may get shorted on the transmission bracket which would blow the fuse. This keeps the alternator from charging the battery.
The new cable part number is: A203 440 88 32 Positive starter/generator cable.
Ok so i just got a use but like new alternator on my 2011 chevy cruze and a brand new battery
ANSWER : The voltage output of the alternator should be tested at the battery terminals while the engine is running. You should read output of 13.8 volts on up to maybe 14.4 volts but the value (and range, which is dependent on engine RPM) will depend on your Factory Service Manual Specification which the Mechanic will have on hand. You also have to look at the output while running various circuits. It could be that there is a short in one of those circuits which causes battery voltage to drop below the threshold at which the warning light will set. My initial suspicion would be the alternator is simply out of spec. What I would recommend is having a certified professional from YourMechanic perform an inspection of your battery and charging system which will identify the root cause of this issue you are having. Once the cause is understood, he or she will explain the repair strategy and cost. Please let us know how we can assist you further or if you have additional questions.
installed new alternator and battery the alternator is charging the battery and the battery is maintaining afull charge but the ba
ANSWER : Hello. If the battery and the alternator are new and if it is verified that the alternator is charging then you have an issue with programming. When you replace the battery on this vehicle the computer needs to be reprogrammed to recognize it and to properly charge it. If this is not done then the computer will not turn on the alternator at the correct times an this battery light will come on. You need to have this programming done by a certified mechanic, like one from YourMechanic, who can come to you to [program the battery into the computer] https://www.yourmechanic.com/services/battery-light-is-on-inspection
