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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13
votes
4answers
205 views

Can a weak battery destroy an alternator?

I've heard a story that a weak vehicle battery can destroy an alternator or cause an alternator to fail early. Is this true, or is it largely fiction?
10
votes
5answers
926 views

Can a car AC unit be run on just the car battery?

This might be a silly question but I was wondering if a car AC unit be run off entirely on battery or alternator? As this could help in Preventing power loss during important times such as ...
10
votes
2answers
1k 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 ...
9
votes
6answers
9k 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 ...
9
votes
2answers
339 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 ...
9
votes
4answers
9k 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 ...
8
votes
1answer
60 views

Connecting to the Battery During Emissions Testing to Measure RPMs?

When doing emissions testing, they connect to the battery, either directly, or using the cigarette lighter socket. I'm assuming that this is to measure the RPMs, as the only other thing connected ...
7
votes
4answers
41k 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 ...
7
votes
2answers
242 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
6k 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
1answer
809 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 ...
7
votes
2answers
100 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 ...
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
615 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 ...
7
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 ...
7
votes
2answers
62 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
14k 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
9answers
3k 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 ...
6
votes
3answers
790 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 ...
6
votes
1answer
60 views

Alternator whines when it's cold, 2000 Toyota Camry (5S-FE engine)

I have a 2000 Toyota Camry with the L4 5S-FE engine. The car has 140k miles on it. When I first start it, the alternator whines fairly loudly. I narrowed it down by ear, then used the typical ...
6
votes
3answers
374 views

Kawasaki EX650 - What causes 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 ...
6
votes
1answer
71 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
114 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
424 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
206 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
0answers
73 views

Alternator isn't charging battery properly. Replace or swap regulator only?

I have a 2015 Honda Fit EX. On my dashboard, there is a small screen that has been displaying "CHECK CHARGE SYSTEM" and displaying warning lights (TPMS, power steering, and stability control). I ...
6
votes
3answers
457 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 ...
5
votes
1answer
88 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 ...
5
votes
3answers
176 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. ...
5
votes
1answer
55 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 ...
5
votes
1answer
133 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
64 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
9k 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 ...
5
votes
3answers
640 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
52 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
1answer
1k 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
0answers
30 views

VW Transporter T5 - p1503 Generator Terminal DF (Load signal) Signal Improbable

I have a VW Transporter T5 2007 with 2.5 TDi BNZ engine. I have the following fault code (among many): p1503 Generator Terminal DF (Load signal) Signal Improbable. This fault code gets repeated ...
4
votes
4answers
171 views

How to replace Alternator out (2001 Nissan Sentra) [pictures inside]

I am trying to remove the Alternator on my Nissan Sentra 2001. I believe I need to take the alternator belt off. It's tightly on the pulley - see picture How to make the belt loose? I am told that ...
4
votes
3answers
423 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
1answer
40 views

one wire alternator

I have a one wire alternator on 350 Chevy V8 in a 57 Belair. After charging the battery and running the car for about an hour the battery will run down. Changed the alternator but no difference. ...
4
votes
3answers
693 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 ...
4
votes
2answers
10k 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
43 views

The Testing Procedure for the Mazda 626 Alternator in the WSM is Unclear

I have some questions regarding the alternator testing procedure outlined in the 98 US work shop manual ( this is related to my battery warning light question ), my car has the FS engine: When it ...
4
votes
2answers
19k 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 ...
4
votes
1answer
3k 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
99 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
91 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
2answers
7k 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 ...
4
votes
1answer
55 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 . ...