Driving with an overcharging alternator. Any Ideas are appreciated. Dec 27, 2022 · When an overcharging occurrence is severe, driving for extended periods of time can lead to expensive electrical system repairs that are significantly more expensive than changing the damaged alternator. My '66, 240, A/T, had a unique smell on the way home last Thursday. Nov 11, 2022 · The voltage regulator controls the voltage the alternator generates, it doesn’t control it after the current is produced. If the shop disconnected the battery while the vehicle was running, the voltage spike could do this. Jun 28, 2023 · When your alternator is overcharging, it can cause your taillights and headlights to blow out prematurely, one at a time or at the same time. Battery overcharging in the 2006 Five Hundred SEL typically stems from a faulty alternator voltage regulator or damaged wiring. Imagine driving with a constant check engine light, flickering Mar 4, 2025 · The car alternator continuously charges the battery while the engine is running, ensuring that the battery maintains enough power to operate the vehicle's electrical systems and to start the engine for the next use. 5-15. i replaced the everything, including the external regulator. Mar 30, 2025 · The Perils of Overcharging While a properly functioning alternator keeps your battery topped up, an overcharging situation can wreak havoc on your car’s electrical system. should i bother with taking it off and testing it or is it shot? most of the winter it was overcharging a little and it worried me but always evened out. A battery light illuminated on the dashboard indicates a charging system issue. However, installing a new alternator may be a more feasible alternative. While driving the voltage reads about 15. Charging System Service Now is the message that comes up on the dash screen. It empowers you to diagnose potential issues early, preventing costly repairs and unexpected breakdowns. to/3NebLCc - All-in-One OBDII Scanner In this short video we will talk about alternator overcharging. 2 volts. Feb 23, 2018 · I was driving to work this morning and about 5 minutes in check gauges came on and my voltage gauge was pegged out. Jan 14, 2021 · 2015 - 2020 F150 - over charging alternator - Because I have a 1953 f350, I usually follow that group. Jul 8, 2024 · The alternator, which is also known as a generator, makes electricity that powers all the electric accessories while the driver is on the road. Not understanding how the system works can confuse you into thinking the alternator is bad Jul 16, 2025 · Can an alternator charge a car battery? Yes, but it depends on several factors. If you suspect overcharging, stop driving and inspect the charging system immediately. But how do you know if your alternator is the real culprit behind your battery woes? In this article, we’ll delve into the Dec 2, 2022 · The alternator supplies direct power to most of the electronic components of a car. Its have an overcharging issue. Keep your car running smoothly! Nov 2, 2022 · Driving with an overcharging alternator increases the risks of damage to the electrical components, primarily light bulbs, and the battery. ) The car has 72000 miles on it. There is no fluctuation while driving, accelerating or deceleration - the gauge needle goes past the midpoint upon start up. Additionally, symptoms of an alternator that is overcharging include ongoing blown fuses, interior lights that blow out, and lights that get extremely bright when you increase the speed of your engine. 41 is for alternator field issue, and 46 is for overcharging. How much easier could it be could it be because I ran my Jul 17, 2010 · I have 2007 volvo 780 with cummins isx, my alternator starts overcharging when driving in rain or wet pavement. This article delves into the underlying causes, detrimental effects, and effective solutions to address car alternator overcharging. But just like the alternator can undercharge the battery, it can also overcharge it, which can cause significantly more damage. However, the electric charge must pass through the voltage regulator. I know the PCM controls the charging . If the voltage regulator is not sending the required voltage needed to keep the battery charged, the car will die while driving down the road. Mar 30, 2023 · This article discusses the causes of an overcharging alternator and offers tips and advice on how to identify the signs and symtoms. 0 motor that I am looking for some help on. 0 liter engine). We’ll discuss the signs of a failing alternator and tips for preventing battery damage, ensuring your vehicle runs smoothly. Residual magnetism in coil maybe? Any advice? I'm starting to suspect that the new alternator is also faulty. Today, I started the truck, had the (bus) issue where the radio doesn't Alternator overcharging is not safe or suitable for your vehicle. Overcharging can damage the battery’s internal components, reducing its lifespan and potentially causing it to fail prematurely. My voltage gauge was pegged 18+ volts. I had cleaned the grounds and it seemed like it was fixed. Here are the causes and fixes of alternator overcharging with symptoms. Mar 28, 2021 · I have replaced both the Battery (Duracel AGM) and the Alternator (Bosch reman) on my 2005 Escalade ESV (6. Since then, I replaced the fan harness (the 'new' new one is fine), and up until today, my charging system was fine. Thanks for the timely response. 5 volts, so anything greater than 14. Temp also plays a factor in charge voltages. 3 Its been a great truck but a few weeks ago I noticed that my alternator was over charging at around 15. Can 19V from alternator really short all the parts at once and how likely is it )) Yes. There is one fuse to the alternator voltage regulator and one fusible link from the alternator to the battery An overcharging alternator can do a lot of damage. Mar 15, 2018 · My 2007 Classic Silverado has over harged since new. I tested the alternator and battery to make sure that my inside voltage indicator was right and all three of them May 9, 2025 · Why is my alternator overcharging? Discover common causes and symptoms, ensuring your vehicle runs smoothly without electrical issues. Start by testing the alternator output voltage with a multimeter; it should be around 13. It happens when I accelerate. An alternator producing too much Jan 23, 2024 · An alternator overcharging means the alternator voltage regulator has failed, causing excess voltage to be sent to the battery and electrical system. Imagine replacing your car’s battery, only to have it fail again within days. Think of it as the main generator that keeps everything running when your engine is on. What's the best way to throttle back the the charge so it hits where it's supposed to on the gauge May 26, 2025 · The alternator is a vital part of your car’s electrical system. All my electronics and everything else is working normally. Any suggestions? In this video we'll talk about the causes of alternator overcharging and what you can do to prevent it and fix it once it's happened. When one fails, the other often suffers the consequences. Resting voltage of battery is in the 12s (while truck is off but connected to terminals). Anything over 17 volts is enough to take out the electronics. 5. 2V or so to the battery Symptoms of an Overcharging Alternator Battery Light or Battery Message Battery bulging and hot with strange smell How To Tell if Alternator Overcharging Check battery voltage with engine running. Oct 7, 2024 · Car battery overcharging happens when the voltage exceeds 14. To avoid being stranded due to alternator problems, you need to know what can damage an alternator to prevent it. Battery and Terminals Check: Inspect the battery condition and terminals for corrosion or loose connections. I have taken it to a couple shops and they both said the You are correct, 18 volts is much too high, but an alternator can not cause over-charging unless it is assembled incorrectly with one of the brushes grounded through its mounting screw. The voltage regulator doesn’t “send 17 volts to the alternator”, it’s causing the alternator to produce it (and it shouldn’t). It could be a problem with the alternator, the battery itself, or a wiring issue. Make sure your car’s battery terminals are free of oxidation and are making good electrical contact with the terminal connectors. Modern vehicles are increasingly reliant on complex electrical systems, making the alternator’s health even more crucial. Mar 27, 2025 · If your battery frequently overheats or swells, have your alternator and voltage regulator checked. Does Feb 15, 2025 · Overcharging occurs when the charging system in your car delivers more electrical current to the battery than it can safely handle. Without a functioning or with an underperforming alternator, the car will drain the battery after no more than a couple of miles of driving. But after letting it sit for 8hrs for the BMS system to learn the battery it seemed to work fine. It will stay there for about 10 seconds and then go back to normal and the light will go off. Imagine driving at Jan 10, 2025 · Especially if you are not driving for a long time, knowing how to tell if your alternator is overcharging and how to fix an overcharging alternator can save your car and also save your money. The alternator, in turn, gets its electrical energy from the rotational force of the camshaft pulley and alternator pulley, which are connected to the engine using a drive belt. Rick, take your Jeep to a mechanic or autoparts store and have the alternator checked. the first time it messed up my battery then blew the alternator. Find out if you can drive with a bad alternator, its signs, replacement costs, and more. 9-15v. An overcharging alternator in the Silverado 1500 can cause high voltage readings, risking battery and electrical system damage. Nov 2, 2011 · so i am having overcharging problems, again. Nov 22, 2024 · While this symptom can also indicate battery or alternator issues, a faulty voltage regulator often causes a distinct pattern: lights get unusually bright (indicating overcharging) followed by dimming (indicating undercharging). Nov 20, 2022 · An overcharging alternator, or alternator that produces too high of a voltage, can be caused by various factors and lead to damage to the battery or other components if left unchecked. Overcharging can also affect an alternator even though it is less common. 8 volts. But I also have a 2016 f150 with a 5. Now I had the old alternator tested and it passed three times. After driving for a while, meter measured Voltage output just above 15. 2 days ago · Is your alternator overcharging for some reason? Is it caused by a bad battery? Here are the main symptoms, the possible causes and how to fix it. Oct 18, 2023 · In the most severe of cases, driving for sustained periods during an overcharging event can necessitate costly electrical system repair, which far exceeds the cost of replacing the defective alternator itself. Smelled like roofing tar. 3. Jan 14, 2013 · Hi Everybody, Recently noticed that my voltage in my truck is very high. Learn the warning signs, causes, and how to fix or prevent overcharging today. Even after replacing the alternator, inspect the voltage regulator integrated within it. You can also do a voltage drop test on the cables to determine their health, they should be less the 1 volt on each. This comprehensive guide will provide you with step-by- step instructions on how to test your alternator using a multimeter, empowering you to Sep 1, 2024 · An overcharging alternator can cause battery damage and other issues with your vehicle’s electrical system. Discover the signs, symptoms, and prevention tips to keep your car’s electrical system in good condition. Check for corroded or loose ground wires between the alternator and battery. Overcharging occurs when the alternator generates more electricity than the battery can handle, leading to an excessive buildup of charge. A failing alternator can cause the battery to work overtime, leading to premature wear or even complete failure. I have replaced alternator twice, replaced batteries twice as well in last 6 months ( at dealers). Jul 16, 2021 · No, as a general rule, you should not drive your car if the alternator is continuously overcharging the battery. Oct 4, 2023 · Read on to learn more about alternator overcharging, as well as its causes and a comprehensive how-to guide on how to diagnose and fix an overcharging alternator. Does the alternator have a voltage regulator? Or is the voltage controlled by I'm working on a 93 XJ 4. The alternator was replaced earlier Nov 14, 2022 · There are a few reasons your car battery might be overcharging. It may also cause all kinds of problems with the onboard electronics and computer controls. An overcharging alternator can do a lot of damage. Its Hella branded one. Not mine though. If the voltage regulator within the alternator fails, it can lead to overcharging the battery, which in turn causes excessive current to flow through the alternator wires, leading to overheating and melting. Is the alternator is overcharging, it can put extra strain on the engine block and potentially cause problems with the engine running smoothly. 2 to 15. However, today I was charging the AC system and it started doing it again. An alternator may get overcharged and disrupt a car’s functioning. If your mechanic suspects that the alternator is overcharging, they will test the voltage output of your alternator to ensure it’s charging at the Dec 14, 2015 · I have a 2006 Buick LaCrosse with the 3. Last week I found out that the alternator was overcharging (charging at around 15. https://amzn. Apr 25, 2025 · To fix an alternator overcharging problem, you must remove and have the alternator repaired by replacing the built-in voltage regulator (VR). Can an overcharging alternator damage your car? Absolutely. Oct 7, 2002 · C3 Tech/Performance - gauge says iam overcharging with new alternator ? - Hello I put a new alternator on my 76 this weekend and took it for a drive my voltage gauge is almost maxed out when I am driving. Got home and you could smell the cooking alternator (smoke was comming off this thing) Can anything outside of the alternator make it go crazy like this or is the alternator bad? I have Jun 10, 2025 · As a car owner, there’s nothing more frustrating than waking up to a dead battery or experiencing a sudden loss of power while driving. As I was driving I noticed that light did get brighter at revs and at home I measured battery voltage with alternator 2-pin plug unplugged. 8-14. How long can I drive with a bad alternator? It’s not recommended to drive with a bad alternator. In this video you will learn the common causes, why the battery is overheating and repairs to fix the issue. I do have subs though but usually the voltage should drop. to/3WtNBGE - Alternator testers https://amzn. I have a plug in Mar 16, 2017 · So over the past 2 days, my Arc Audio XDi 1200. Jul 18, 2005 · Driving home tonight my lights went crazy bright and my alternator light came on. I've also caught it periodically drifting to about 16 volts momentarily. A bad ground can trigger a false battery charge level, which will cause the alternator to overcharge while trying to respond to a false situation. Your alternator might be overcharging due to a faulty voltage regulator, electrical shorts, or a corroded battery. The voltage regulator is shorted, which is fairly uncommon, or the control wire Sep 12, 2023 · Put in a new HO alternator in the Sierra about a year ago, not long after I upgraded to dual e-fans. Your car’s alternator and battery work hand in hand to power your vehicle’s electrical systems. I have a 2010, 1500 with a 5. The generator can undercharge the battery, but it can also overcharge it, which is much worse and can cause a lot more damage. The voltage regulator circuitry inside the PCM is bad. 0 volts could result in a By Geoff Cudd With the numerous connections running through your engine, can a bad ground cause an alternator to overcharge? Yes, a bad ground can cause an alternator to overcharge. This can happen due to a faulty alternator, a malfunctioning voltage regulator, or even leaving your headlights on for extended periods. Aug 2, 2025 · Yes, driving with an overcharging alternator can cause significant damage to your vehicle’s electrical system. It is throwing codes 41 and 46. The alternator is a crucial component of your vehicle’s electrical system, and its failure can lead to a variety of problems. Jul 30, 2021 · I've got a bit of a weird issue with my 2013 Silverado 5. Jan 12, 2024 · When the battery voltage consistently remains above the normal range while driving, it indicates a potential issue with overcharging or a faulty voltage This can be caused by a variety of factors, including a malfunctioning alternator, a faulty voltage, or a problem with the electrical connections. Dec 5, 2024 · Wondering if your car alternator can overcharge the battery? Learn how this happens, how to spot the signs, and what you can do to fix the issue before it causes damage. Most voltage regulator components built into alternators limit output at approximately 13. Inadequate Wire Gauge The gauge of the wire used in the alternator circuit must be suitable for Mar 17, 2022 · Overcharging: An alternator that is overcharging may result in short bulb life. Anyone experience this? Leaving it with my audio guy next week while im in the Bahamas so he can get it all fixed but wondering if Jul 21, 2023 · This is important because a bad battery could make the alternator overcharge, thus making it difficult to determine if the alternator is bad. 3L that I've researched but haven't found anything about my specific issue occurring. One of the most common culprits behind this issue is a faulty alternator, which can slowly drain your battery, leaving you stranded. When I went to idle the voltage would drop to 14 but went right back up when I drove. Jan 21, 2016 · Escape & Escape Hybrid - 09 3. That’s because an alternator overcharge will happen if the VR is faulty. Over-charging is caused by the voltage regulator driving the alternator too hard. It’s important to have the alternator checked if you suspect overcharging. If you have a decent local shop, they should do a basic battery alternator test for you, and that would be a bit more thorough then just a dvom reading. Battery is good. Jan 17, 2011 · Could the alternator be overcharging because the battery was ruined from initial overcharge? This is the second battery, the first that leaked was tested and was dead so was replaced. This extra strain can lead to premature wear and even complete failure of the alternator, which is both expensive and inconvenient. If this is indeed your problem, you have been lucky twice. 8 and up to 16. 0 alternator overcharging - Hi, my 2009 Escape, 3. It was charging around 16 volts. The voltage will read 15+ volts once in a while it will drop to normal 14 volts but a couple times it would drop to 12 volts and stay there until I turn of the truck and restart it and it will read 15+. The problem im having is the battery gauge shows a spike ( normal reading shows guage at half way And the spike goes almost 3/4 of the way for a few secs and goes back to normal). I checked this morning and the light is out, no codes, and the running battery voltage is 15. If you suspect alternator problems, it’s essential to test it promptly to identify any potential issues. An overcharging alternator will cause damage to the battery and wiring of the charging system. Denali starts and drives fine. 9, key off, i eased the clutch back out 2004 - 2008 Ford F150 - OverCharging alternator - Hi im new to the site. A failing alternator can place undue May 9, 2008 · 1961 - 1966 F-100 & Larger F-Series Trucks - Alternator overcharging!!! - Well, I'm stumped once again guys. Reader says this is High. It was whining so I got a new one anyway installed it and it is actually reading higher 16+ volts. If that is the case, the 15v charging isn't the problem, your problem is a parasitic drain and you're testing an alternator that is overworking to charge the battery up fully. Oct 21, 2012 · Sometimes while driving my 2001 Cherokee the voltage gauge will max out at 19 volts and the check gauges light will come. 7 volts. At the other extreme, a battery that is sulfated due to being undercharged or not seeing constant use will maintain normal charging voltages. May 30, 2024 · Is your car battery acting strange? Learn the telltale signs of an overcharging alternator. I hope this article helped you understand the relationship between your alternator and car battery. Mar 21, 2024 · Do you suspect that your alternator is overcharging? Learn about the symptoms, causes, and some common fixes for this issue here. However, when it malfunctions and overcharges, it can lead to severe consequences for your vehicle’s electrical system. If you'd like more info Oct 15, 2023 · Wondering if a bad alternator can damage your battery? In this post, we explore how a malfunctioning alternator can lead to battery issues, including overcharging or undercharging. I replaced the alternator with one that I got from a salvage yard (to save money) but it is still over charging at the same voltage. On modern vehicles, an overcharging alternator may result in an illuminated check engine light. Then after Mar 30, 2023 · This article discusses the causes of an overcharging alternator and offers tips and advice on how to identify the signs and symtoms. Allowing an alternator to continually operate at high voltages above 15 volts Jan 13, 2025 · An overcharged alternator can damage your battery and electronics. There's two possibilities for this condition. Apr 9, 2019 · My truck is a 1500. Our guide explains symptoms, easy fixes, and how to save your battery from damage. Feb 26, 2014 · Sounds like the alternator is seriously overcharging while you're driving. Mar 14, 2025 · How to Diagnose Alternator Issues Here’s a guide to diagnosing common alternator faults: Check Dashboard Lights: Start with the engine running and observe the dashboard lights. 0L. The battery was sizzling!!! It was burning up hot, When an overcharging occurrence is severe, driving for extended periods of time can lead to expensive electrical system repairs that are significantly more expensive than changing the damaged alternator. Apr 12, 2025 · Yes, a bad battery can indeed ruin an alternator. Regular maintenance and using smart chargers can help prevent this issue. And excess voltage can build up quickly. Sep 23, 2024 · A functioning alternator is crucial for maintaining your vehicle’s electrical system and ensuring a smooth and reliable driving experience. Car dies while driving. 4 FX4. Mar 8, 2024 · When it comes to the Ford F-150, alternator failure can be a common issue that many owners face. also bought the truck with Are you jump starting the car? What do you mean the "car kept dying". When a car battery is weak or failing, the alternator is forced to work much harder than normal to compensate for the lack of electrical power. Rare, but possible. By following proper battery maintenance practices, charging procedures, and addressing any electrical system problems promptly, you can protect your battery’s health and ensure a reliable May 4, 2025 · Yes, a bad alternator can kill a brand new battery by either overcharging it or failing to recharge it properly. In this article, we will explore the causes, symptoms, and solutions for Ford F-150 alternator failure, helping you better understand this issue and how to address it Apr 1, 2025 · Learn how to test your alternator with a multimeter, load test, and visual checks to avoid battery failure and costly repairs. 0, had a random battery light on last night. 5 volts. What happens is sometimes I start the truck cold and the dash gauge will show it charging at 14+ volts even with AC and lights on. Identify the symptoms of an overcharging alternator and what you can do before any other components get damaged. Thanks in advance. Jan 15, 2025 · When we got back I got a new alternator and battery and installed them and it seemed to still be charging pretty high at around 14. The excess voltage can fry sensitive electronics, damage the battery, and even cause a fire. May 25, 2014 · Diagnosing charging system problems on a GM vehicle equipped with the EPMS system The EPMS system monitors battery usage with the battery current sensor. I recently got a new battery (within the last 2 months) I find it hard to believe A bad alternator can kill your battery and leave you stranded. Is it safe to drive with an overcharging battery? No. if i recall correctly the battery was getting around 15. It was still overcharging. Not only does it recharge your car’s battery after you start the engine, but it also supplies all the electrical power your car needs while you’re driving – for lights, radio, wipers, air conditioning, and all the onboard computers Nov 15, 2023 · Faulty Alternator Alternators with internal faults can produce irregular charging voltages. Without wasting much time, Let’s see some of the noticeable symptoms of an overcharging alternator. Learn how alternators work, how they charge batteries, and what to do when they fail. Had the alternator replaced once a d still over charges. Dec 9, 2019 · addtnl information: I am not sure on the control side of the alternator, I tried something today while driving, 65mph, down hill some, i turned the key off and the alternator kept charging, so to stop that, clutch in, engine totally stopped, voltage reading on my inverter display settled at 13v then to 12. These components include the radio, electric steering, windshield wipers, headlights, and heated seats. Got home, popped the hood just for a weekly checkover of things. This can quickly damage a new battery and cause wiring harnesses to melt or catch fire if left unaddressed. Timecode: 00:00:00 - Short intro 00: May 4, 2025 · Yes, a bad alternator can mess up a battery by overcharging, undercharging, or completely draining it. after the repair i was getting around 14. Alternator Overcharging the car battery symptoms. 8 L motor. Feb 24, 2025 · Do I need to worry about overcharging my battery from the alternator? Overcharging is a concern if the alternator is malfunctioning, as it can damage the battery over time. How long after starting Oct 6, 2024 · Learn how an overcharging car alternator can damage your battery, causing overheating, reduced lifespan, and costly repairs. 2V. You don’t have to stop immediately and call a towing service, but you shouldn’t drive your vehicle normally either. Jun 23, 2025 · Understanding how to check your alternator’s charging capabilities with a multimeter is an invaluable skill for any car owner. 5-14. It sounds like you are saying the battery is dead if you don't drive it daily. May 11, 2013 · Hi - my battery gauge is showing the alternator over charging a bit. Driving with a bad alternator will cost you your car battery. May 4, 2025 · Yes, a faulty alternator can send too much voltage to the battery, leading to overcharging. Mar 16, 2025 · Understanding the science behind battery charging, the role of the alternator, and the warning signs of overcharging is crucial for preventing these issues. Driving with an overcharging battery increases the risk of battery explosion, electrical failure, and fire. I have a 2006 F-150 5. This can lead to flickering lights, dashboard warnings, and even frequent bulb replacements. A weak or faulty battery Dec 12, 2014 · Most often if a regulator dies, the alternator will stop charging the battery, or will have a drop off at RPMs above idle. In some cases, it can fail, causing an overcharge. If the car's generator doesn't work or doesn't work well, the battery will die after only a couple of miles of driving. I can't see where I could have gone wrong with the install. Today this problem started again, this only happens during conditions, it will start charging normal as soon as i get into dry condition. Can a Bad Ground Cause an Alternator To Overcharge? Try to buy a quality alternator for your car; this will save you more money in the long run. Dec 9, 2022 · Hello all, I need a little help/advice. 6 has gone into protect mode (Code 14 - Over Voltage - Alternator Overcharging) 4 times. 7 volts, leading to overheating, corrosion, and potential failure or explosion. The work of the alternator is to recharge the battery as you are driving. Based on the data from the current sensor and the charging conditions listed below, the body control module (BCM) determines the best charging routine. Aug 30, 2024 · A car alternator is a crucial component responsible for recharging your vehicle’s battery while driving. Very likely. Feb 25, 2016 · Because normal charging voltage can’t be achieved on a battery with a bad cell, the alternator will overcharge the remaining cells and boil the electrolyte. I do live at 7500 feet elevation (don't think this matters, but Sep 24, 2021 · Unplugged the alternator again and drove home. An alternator’s output is regulated by an internal voltage regulator, which prevents overcharge, but a failure of the voltage regulator, like all things, can and does fail intermittently. uxticb mn i6gu rqzwjm vpwmvy ziv29l hfuyms tpmbhs basx 0kpy