An engine accessory which generates alternating current (AC). The electricity is then fed through diodes which converts it from AC to direct current (DC), which is usable by the automobile in general. The alternator is usually driven by belts which are connected to the crankshaft of the engine which ...

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10
votes
2answers
833 views

Can I safely upgrade to an AGM battery?

AGM batteries are capable of being charged at a faster rate, and may draw additional amperage from the alternator if it is not regulated. Many cars that come with AGM batteries have special charge ...
8
votes
2answers
183 views

Non-functional gas pedal, engine stalling, dead battery: broken alternator?

I have a 2005 Nissan Sentra. The following happened twice within a few days: I stopped at a red light. When the light turned green, pressing the gas pedal had no effect at all. However, the car ...
8
votes
4answers
7k views

How to assess battery charge level and alternator performance?

What diagnostics can be done to to assess battery charge level? I'm interested both in one-off tests like can be done in car service and also continuous monitoring during normal use. Car panels ...
7
votes
2answers
223 views

Is any power from the alternator 'free'?

Cars generally (and specifically a Honda Accord 2002) are not very energy-efficient. Given all the inefficiencies, is it "free" to plug in, say, a smartphone into a car to charge while I am driving? ...
7
votes
2answers
5k views

Can an engine stop from a bad battery?

The car is a 2005 Toyota Corolla CE. Its engine is the 1ZZ-FE, a 1.8L straight four that runs on gas, not diesel. The alternator is stock, and tests out just fine on the multimeter in both voltage ...
7
votes
3answers
3k views

Does idle RPM increase when there is heavy load on the electrical system?

I am thinking about installing a 500w halogen (HDX brand) on the roll bar in my jeep as the dome light because often I work in the back when it is dark or when I would like more light. The 500w light ...
7
votes
2answers
46 views

Can long term parking affect alternator?

My neighbor just told me that his mechanic informed him that leaving a car parked long term not only effects the battery, but can also deteriorate the alternator. The battery having issues makes ...
7
votes
2answers
12k views

Failing alternator, idler pulley, or something else?

I have 1997 Chevrolet Lumina sedan. I’m trying to diagnose a sound coming from my engine. It is a “whirring” noise that varies with the engine speed (e.g., if I accelerate, the sound becomes louder ...
6
votes
5answers
6k views

Noise in stereo that changes pitch with engine RPM

This is a question of curiosity. I have a '98 Acura Integra, a cheap car stereo with a 3.5mm aux in, a cheap inverter and a smart phone. If I have the smart phone audio hooked up to the car stereo and ...
6
votes
2answers
77 views

Battery and Alternator Pass Test - 2003 Mustang GT

I have a 2003 Ford Mustang GT, I had the battery tested and it will take a jump and start up so naturally I am thinking the alternator is bad. I take the alternator out and have it tested 3 times and ...
6
votes
2answers
577 views

How to detect a failing car alternator..?

Is there some way we can predict that the car alternator is about to fail in order to avoid a discharged battery situation on the road.. Although it will slow the sound of horn and will dim the ...
6
votes
1answer
50 views

Alternator grinding - Is it OK to drive to mechanics?

I have a 2000 Suburban and the alternator is making a grinding sound. The Suburban still starts up and I am wondering if it could harm other engine components (like the serpentine belt) trying to ...
6
votes
1answer
46 views

Battery light on after new alternator

Car: 2003 Honda Civic Si G1Wh dash cam, 400w amp, 4300k HIDs My alternator failed badly (stereo cutting off), no battery light. Replaced it with a reman Duralast, battery light is on. It shows 14.5v ...
6
votes
1answer
340 views

Alternator, Battery, or Fluke?

While we were out running errands yesterday, our car failed to start after a half hour stop at one of our destinations. The first attempt to start the car resulted in nothing but a rapid clicking ...
6
votes
2answers
178 views

Alternator vs Battery

I hadn't used my car in a week. Normally it always starts. Then one day after one week it didn't start. I got a jump from my neighbor and i was able to drive around for more than 20 minutes. I stopped ...
6
votes
1answer
1k views

Why would turning on the A/C affect my alternator output voltage?

So yet another chapter unfolds in the A/C gremlin saga of my LS1 Chevy. Backdrop A/C compressor is relatively new (2 years old) One of the belts is squeaking (not sure which one) Recently performed ...
5
votes
8answers
2k views

2 Volts on Car Battery

My car battery has gone completely flat after leaving my car parked up for about a month. Tried turning over the car today, and none of the lights on the dash light up. Ran a multimeter across the ...
5
votes
1answer
80 views

Burning Rubber while driving and after

Tonight I popped out in my partners car and noticed an awful burning/chemical smell whilst driving, this smell got worse if you turned on the AC (FAN BLOWER), so I got her to pull over and had her pop ...
5
votes
2answers
59 views

Jeep electrical/charging problem

I have an electrical problem with my 96 Jeep Grand Cherokee. The alternator whines and the battery gauge drops to zero. I put a new battery in and a new alternator and it didn't fix the problem. any ...
5
votes
3answers
596 views

93 Nissan Sentra SE-R, replaced alternator voltage still low

My car died while I was driving it, but I can put the battery on a charger (or from another car, with jumper cables) and get it running albeit for a short period of time. I put a multimeter on the ...
5
votes
1answer
34 views

ECM Fuse Blown what to test next

Recently I was on the highway and suddenly my car broke down and it was cranking and all but not starting so I knew some fuse has blown. I removed the indicator fuse and used it for fuse which gave ...
5
votes
3answers
178 views

What might cause a stator to burn out?

My motorcycle recently required a new stator (plus a new regulator rectifier and battery) because the stator burnt out and fried everything. What are the typical causes of a burnt-out stator? Does ...
5
votes
1answer
863 views

Can a bad battery damage voltage regulator?

I have a '91 Ford Sierra Saphire 2.0 OHC (pinto). Have been struggling with having no charge for weeks now. I've tried two different alternators, had one of them completely rebuilt by a professional, ...
5
votes
3answers
366 views

Alternator draining battery

My alternator has been draining my battery in my Datsun 240z since I swapped the engine (VQ35). It takes around 4 days to drain the battery to the point I can't start it. It charges it fine when the ...
4
votes
4answers
37k views

How to diagnose a starter motor that does not work

My e46 M3 would not start when I got to the parking garage after work. When I first turned the key, I heard a sound like grinding gears, but I was so startled that I immediately stopped trying to ...
4
votes
3answers
313 views

Engine Mounts issue can be caused by replacing Alternator?

My mechanic recently replaced the alternator on my 2007 Toyota Camry. When he returned the car to me he said that my motor mounts need to be replaced. Now I notice a vibration at idle. I am not a ...
4
votes
2answers
8k views

Mustang charging system warning light on, but battery and alternator both passed testing?

I have a Mustang that the battery light stays on. I changed the battery and the alternator was checked by Autozone, they said it was good. I need help
4
votes
1answer
48 views

What are slip rings with respect to a cars alternator?

This is not a physics forum, and as such I don't expect answers to explain Faraday's law of induced emf (electromotive force), which is the basic physics principle behind how an alternator is able to ...
4
votes
1answer
50 views

2002 golf dead battery - Was able to jump - Bad alternator or Battery

I have a 2002 Golf. I put the car on the drive on Friday night and tried to use it on Wednesday and it was dead. No lights, no display nothing. I came home and jump started and it ran fine. No stalls ...
4
votes
1answer
699 views

DIY Alternator Belt Tensioner

I've got a diesel engine in my boat, but the previous owner had somehow snapped the alternator bracket, and fitted it fixed to the boat rather than the engine. Now the alternator doesn't move when the ...
4
votes
1answer
2k views

How to repair alternator slip rings to stop squeaking?

Background I have a new Bosch CS-130 style alternator with a couple hundred miles on it. Since I installed it, it's been a little noisy, but I attributed that to the brushes breaking in to mate with ...
4
votes
1answer
49 views

Battery light flashing after alternator install on 2004 Ford Escape

I just put new alternator on my 2004 Ford Escape, and now my battery light keeps flashing on and off, and it will sometimes stay on. The battery has been checked and is charging 100 % . The alternator ...
4
votes
2answers
3k views

What is the correct/factory wiring for a Suburban 1998 battery/alternator?

I have included a picture showing what I have now on this Suburban. Note that there is wiring not shown in the picture which is a second electrical connection to the positive side of the battery ...
4
votes
2answers
85 views

1998 BMW 318is excessive current draw - possible starter issue

My 1997 BMW 318is started making a whirring noise that varies with engine speed, and an electrical burning smell after driving, and the battery goes flat very quickly. I measured the current draw ...
4
votes
1answer
84 views

Alternator/Battery power question

Good Afternoon, I have a 2014 Ford Focus SE that i use as my Work Vehicle. I work in Emergency Roadside Assistance. I have to run a laptop In the car in order to direct calls to other employees and ...
4
votes
2answers
7k views

How can I clean the dirt build-up in my alternator?

The alternator in my '04 Lumina SS is its Achilles' heel. It lasts a few years before it starts to overcharge the battery, after which the only practical remedy is to replace it. While I cannot be ...
4
votes
1answer
286 views

How long should fusible links be?

I've installed a 12" fusible link as a replacement for a fusible link on the line that charges the battery from the alternator. I showed the OEM part to the guy at the parts store and he gave me a 12" ...
4
votes
0answers
45 views

Hyundai Accent Diesel 2002 alternator works on day but not when headlights are on

I have purchased Hyundai Accent diesel 2002 four cylinder from my savings .. its start every morning but not at night when the car's headlights are on. I couldn't start it after one or two attempt . ...
3
votes
2answers
526 views

Will an auxiliary battery hurt a vehicle's alternator?

I am going to be road tripping and living out of my SUV for a while. I need a way to power a tiny portable cooler/fridge 24/7 and would like to be able to power my cell phone, laptop, and maybe a few ...
3
votes
1answer
3k views

Battery dash light comes on when starting car then disappears while driving

2002 Honda Civic EX here. When I start my car, my battery dash light has been staying on usually until I get onto the highway, then it will turn off. If I hit a stop sign or red light, then it'll ...
3
votes
2answers
711 views

'03 Mazda Tribute needs jumped every time it starts

I have a 2003 Mazda Tribute. I'm not entirely sure what the problem is with the vehicle. I suppose it could be the alternator or just a dead battery, but could also be something more detailed. I have ...
3
votes
3answers
112 views

Should fuel pump noise be changing according to electrical load and RPM?

One thing that bugs me about my car is that the fuel pump noise is fairly inconsistent. Turning on the lights, aircon, defroster, etc. lowers the fuel pump speed and gives a lower pitched noise. It ...
3
votes
3answers
222 views

Is it safe to charge two batteries off of one alternator?

Right now I have a 3000 Watt invertor wired to a 100ah sealed deep cell battery that I trickle charge at night. My plan is to run #6 wire from the battery in the engine to the spare battery so the ...
3
votes
2answers
4k views

Why did my car stall when I used the foot brake?

Preface: I drive a 2004 Peugeot 206, manual On the motorway the other night, one of my tires blew out. I managed to pull over and change to the spare wheel in about 30 minutes (having never changed a ...
3
votes
2answers
58 views

Causes of Premature Alternator Failure

I bought my car brand-new a few years ago, with only 50 miles on it when it came off the lot. It's perfectly stock - no modifications made, though some parts have been replaced for repair purposes. ...
3
votes
3answers
1k views

Toyota Celica battery light on but alternator appears okay on visual/auditory inspection

Today the battery light decided to rear its head on my Celica. I know this normally points to the alternator, but given that I just replaced a bad alternator in my Chrystler, I can tell what a bad ...
3
votes
2answers
15k views

diagnose faulty voltage regulator causing battery overcharging?

I've been having an issue with an '03 Toyota Echo. The alternator died (at least that is what I thought) as the battery kept going flat. I found an alternator at a wrecker and fitted it, and I ...
3
votes
3answers
10k views

Battery light comes on after starting the car. How big of a problem is this?

On my way to work this morning, the battery light came on. I would say it was about 2-3 minutes after I started the car. My drive to work is only a 10 minutes drive, and the light was on the whole ...
3
votes
1answer
6k views

how fast does the alternator charge the battery?

It would appear that the common word of wisdom is that car alternators provide 50A of output. I actually looked at the supposed specs for my 2008 Jetta 2.5L on the internet -- a compact car -- and it ...
3
votes
2answers
155 views

Why did replacing the battery eliminate these symptoms?

I have a 2006 Honda Civic SI. It was slow to crank when starting up, and while driving, electrical systems progressively got worse (radio would turn off and on, power steering would stop, and then ...