Replaced alternator on car 2 times each time shows it’s charging 14v let car run for a little bit then test drive and car voltage
Replaced alternator on car 2 times each time shows it's charging 14v let car run for a little bit then test drive and car voltage Drops to 11.7 and keeps going down till car stalls alternator and battery have been replaced both times as wel and keeps doing the same I've went through checked all the grounds on this car and everything any help would be greatly appreciated thanks.
My car has 103000 miles.
My car has a manual transmission.
Experienced mechanics share their insights in answering this question :
There are reports that the replacement alternators will not communicate with the engine computer and will not charge correctly. I recommend using only the manufacturer approved replacement part. It can be new or remanufactured but approved for use in the vehicle. Some lower cost alternators on the aftermarket will have charging problems since they will not communicate with the ECM on the vehicle and will stop charging.
How to Identify and Fix Common car Problems ?
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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.
Like plenty of other gas-powered vehicles, the Mazda3 uses a 12-volt battery.
Carquest Professional – Alternator: New, 100 Amps (Part No. 11168AN)
The voltage should be between 13.0–15.0 volts. If the alternator does not produce voltage within this range there is a problem in the charging system. Have the system further tested by a Mazda qualified automotive technician.
When the engine is running, your battery should clock in at somewhere between 13.7 and 14.7 volts.
A good alternator should maintain battery voltage between 13.9 and 14.8 volts (14.2 is optimum). Even worst-case, with all accessories turned on, there should be at least 13 volts at the battery.
Look for an ideal alternator reading of around 12.6. Start the car, and look for a reading of between 14.2 and 14.7. A reading of over 14.7 means the battery is being overcharged, while a reading under 14.2 means the alternator is undercharging the battery.
Mazda 3 Alternator | Mazda OEM Part Number L548-18-300R-0B.
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.
Alternator ratings range from about 60 or 70 amps up to 150 amps or more on many late-model vehicles. Some high-output alternators can generate upward of 200 amps. The amp rating of the alternator is matched to the vehicle`s electrical system.
A fully charged battery should read over 12.6 volts. The actual output voltage produced by the alternator will typically be about 1-1/2 to 2 volts higher than battery voltage. At idle, most charging systems will produce 13.8 to 14.3 volts with no lights or accessories on.
Use a voltmeter to check your alternator; rev your engine to 2000 RPM, keep the engine running, and test the battery with the voltmeter. If your voltage goes from ~12.2 V to ~13-14.5 V, your alternator is doing well. If your V stays the same or decreases, that`s a bad sign.
In most cases, the voltage regulator (which is located inside the alternator housing) is replaced in conjunction with the alternator.
Energizer E90 N Alkaline 1.5 Volt Battery (12-Pack)
When the probes touch the terminals while the car is off and the battery is resting, the multimeter display should show a reading of 12.2 to 12.6 volts (full charge). This voltage range means the battery is in good condition for starting the vehicle.
Fully-charged, most car batteries will measure at least 12.6 volts (~13.0-13.2V for OPTIMA YELLOWTOPs), but low voltage doesn`t necessarily equal a bad battery. Modern cars are very demanding from an electrical perspective, even when they`re not being used.
The battery terminal charging voltage must be less than 14.7 volts to prevent excessive gassing. Charging voltages over 14.7 volts can prematurely dry the battery by boiling out electrolyte, and increase risk of a battery hydrogen gas explosion.
Those batteries that are used in deep discharge cycling mode can be charged up to 2.45 volts/cell (14.7V for a 12V battery) to get the highest charge rate, as long as the volt- age is dropped to the float voltage when the charge is complete.
An average car battery has a capacity of around 48 amp hours; when fully charged, it delivers 1 amp for 48 hours, two amps for 24 hours, and so on.
One of the most common problems you`re likely to experience with an alternator is a failure in the bearings. There are needle bearings in the alternator that allow the rotor to freely spin inside the housing, and those bearings can break down over time as a result of exposure to heat and dirt.
The alternator on your Mazda 3 is what provides power to your vehicle when the engine is running.
Most Mazda 3`s have 1 or 2 drive belts and in some instances, it may be called a serpentine belt. The belt needs to be flexible to circulate across pulleys and can be made out of perishable compositions like rubber, neoprene or urethane. The drive belt belt/s is positioned on pulleys and operates under tension.
The positive and negative cables are small and connected to the respective terminals of the battery. The alternator also shows a connection with the `battery charging wire.
Relevant Questions and Answers :
the most relevant questions and answers related to your specific issue
Replaced alternator on car 2 times each time shows it’s charging 14v let car run for a little bit then test drive and car voltage
ANSWER : There are reports that the replacement alternators will not communicate with the engine computer and will not charge correctly. I recommend using only the manufacturer approved replacement part. It can be new or remanufactured but approved for use in the vehicle. Some lower cost alternators on the aftermarket will have charging problems since they will not communicate with the ECM on the vehicle and will stop charging.
My car will not start Intermittently. I purchased a new battery 2 weeks ago and yesterday the car wouldn’t start. Got a jump and
ANSWER : The issue you are having is probably due to an intermittent fault in the starter motor itself or a deficiency in the starter electrical circuit, for example a large voltage drop due to a poor ground or a high resistance connection. These issues can be readily diagnosed and resolved on a mobile basis if you request a hard starting diagnostic. If you request that diagnostic, the responding certified mechanic will get this resolved for you promptly. Based on Toyota’s Factory Service Manual, the battery should not be disconnected if the vehicle engine is running. The battery acts as a large resistive voltage sink and consequently taking the battery out of the circuit, while the alternator is still running, can create a voltage spike on the car’s electrical system which is not good for voltage sensitive components such as the engine computer. If you have further questions or concerns, do not hesitate to re-contact YourMechanic as we are always here to help you.
Car shuts off, won’t stay running
ANSWER : The most common problem on this vehicle is the fuel pump and fuel pump module. If you remove the rear seat that the fuel pump cover is, on the passenger side. Listen to the fuel pump when it is running and when the car stalls your fuel pump will stop running about three to five seconds before the engine dies. Then you’ll know if the fuel pump is the culprit or not.
You can try and replace the fuel pump module first then replace the fuel pump. However, the fuel pump can short the module out, causing both to be bad and would need to be replaced. If you need assistance with this, feel free to contact a certified mechanic who can diagnose your starting issue firsthand and help you fix it accordingly.
Failing to maintain proper voltage after replacing the starter the alternator and the battery
ANSWER : It sounds like you may still be having problems with the voltage regulator maintaining the proper voltage. When the voltage regulator is not working properly, this 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.
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.
My car stops when engine gets warm and while I am driving I stop on red light and car suddenly turn off and I have to hit starter
ANSWER : Hello, from what you’ve described it sounds like you are having several different issues. The starter should have nothing to do with it stalling, but it will have something to do with the car restarting if it doesn’t turn the engine well. The stalling can be from the distributor or possibly a computer sensor.
The scenario where you hit a car from behind may be from another problem, alongside with the idling of the engine. Without knowing the model and engine size of your car I can only say so much. I would suggest having a mechanic do a thorough check of the entire car to check the engine, brakes, and computer systems to see if the problems can be identified and repaired, or at the very least quoted.
Car died while driving so I replaced the alternator and battery and car won’t attempt to turn over. What else could it be?
ANSWER : The initial failure was likely caused by a sudden fuel system (e.g., failed fuel pump) or electrical (including ignition) faiure. Prior to performing diagnostics be sure you have a fully charged battery that passes a load test. Then, confirm that the engine immobilizer system (security system) is not activated thus preventing the car from starting. If the starter motor is not functioning, check for power to the starter motor when the key is held in the "start" position. If there a large voltage drop at the starter motor or no power at all, you may have a faulty ignition switch but you do have to check out the entire starter circuit, which includes grounds, wiring (some of which is very heavy cabling), fuses, relays, the ignition switch and terminations. On the other hand, if the starter motor is getting power but the starter doesn’t work, then the starter is condemned and replaced. If you desire that a certified mechanic resolve this, please simply request a no start diagnostic and the responding certified mechanic will get the problem diagnosed and repaired for you. Please let us know if you have further concerns or questions as we are always here to help you.
Gasoline inside the car?
ANSWER : The first concern is whether you could have an exhaust leak or a fuel leak. If leaks of that type exist, they should be repaired as both are safety hazards. Occasionally, just due to the weather, exhaust fumes can get drawn into cabin air. At no time, however, is it normal for significant amounts of raw gasoline to be in the air, or leaking as a liquid, especially on a modern car which has sophisticated systems to capture any potential fugitive emissions of vaporous gasoline. If this was a one-off incident, and just limited to exhaust odor, not to worry but if you regularly detect the distinct odor of raw gasoline, that should be investigated at once because leaking gasoline is a fire/explosion hazard. As far as damage to personal belongings from exhaust or gasoline vapors, in ordinary concentrations and if the exposure is fleeting, there is no damage potential. The reason is gasoline is highly volatile and so evaporates into the atmosphere. However, if you spill liquid gasoline on materials, the non volatile compounds will be around for a long time and indeed will destroy many common materials as gasoline is a highly aggressive solvent. Most of the hazard from gasoline vapors is not to personal property but rather to your health because gasoline contains known, well documented carcinogens such as benzene. So, the bottom line is fleeting exposure to the vapors will not damage property but will damage your health. With regard to leaks (exhaust or gasoline, liquid or vapor), if you desire a safety inspection performed by a certified Mechanic, dispatched by YourMechanic right to your location, please request a comprehensive vehicle safety inspection and the responding certified mechanic will address all of your concerns and look at the condition of your entire vehicle. If you have further questions or concerns, do not hesitate to re-contact YourMechanic as we are always here to help you.
