A rechargeable device most often made of lead plates covered in an electrolyte and protected by a plastic shell which supplies consistent electrical energy to a motor vehicle. Often referred to as an SLI battery (starting, lighting, ignition). Powers starter motor, lights, and ignition systems of a ...

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44
votes
6answers
2k views

How to maintain a sometimes-used vehicle?

My daily commute changed from 9 miles to 9 feet when I started working remotely. That means I very rarely drive my car much. After a particularly hectic month, I didn't drive for about 4 weeks and ...
31
votes
3answers
30k views

Is there a way to put Prius with dead battery into neutral?

I own a 2010 Prius. It has a dead battery, front facing forward in my garage. I do not have long enough jumper cables. I’ve searched the Internet. Did Toyota really create a car that cannot be put ...
26
votes
3answers
9k views

Jump starting a dead battery: Connect black wire to negative pole of battery or grounded metal?

Most of the advice I've seen for jump starting cars instructs to connect the black wire to a bare piece of metal on the car with the dead battery. However, I've always just hooked up both poles to the ...
22
votes
6answers
78k views

Pros/cons of higher capacity car battery?

I'm shopping for a new car battery for 1998 Subaru Outback (2.5l). For the physical dimensions the battery has to match, I see some variance in capacity (Ah) rating, and in price too, of course. The ...
19
votes
4answers
3k views

How do I test my car battery?

My car still starts fine but when I turn off the car (just the motor . . the key is still in and "on") I noticed the headlights dim to almost off. It's and older car and the headlights don't turn off ...
19
votes
6answers
21k views

Is Start & Stop technology good or bad for my car? (Alfa MiTO)

I was recently in the lucky position to obtain an (almost brand new) Alfa Romeo MiTo, Progression. Like many new cars coming out these days, it has "Start & Stop" technology that turns the engine ...
15
votes
8answers
42k views

Battery drains by itself when vehicle is parked (parasitic draw)

A 1998 Jeep Grand Cherokee has gone through 3 batteries in the last 3 months. While they have all been replaced by warranties, it'd be nice to get the problem solved permanently. I've tested the ...
14
votes
5answers
9k views

Adding a additional battery to car

I have purchased a brand new Toyota Innova. I need to install a a mac mini, 2 laptops and make this car a mobile office. I need to know if I can install another car battery in parallel, and will ...
14
votes
5answers
40k views

What causes battery terminal corrosion?

I put a new battery in my car about 8 months ago. After a problem starting a couple days ago, I found that there was massive corrosion under the battery terminals, so I cleaned them out and ...
12
votes
5answers
65k views

Is it possible to harm your car by giving someone a boost?

This post explains why it's a potential hazard to clip to the negative post on the dead battery when giving a boost. But I've also been told that I could damage the electronics in my own car if I give ...
11
votes
2answers
724 views

What can we reliably tell from an in-vehicle battery voltage display?

The Red Cross division I am with recently purchased a new ambulance. It comes with a touchscreen display in the cockpit where we can control lights, sirens, check the temperature in the back, control ...
10
votes
5answers
523 views

Should negative trickle charger clips be attached to the battery negative terminal, or ground?

I'm trickle-charging a car using direct connections to the battery. I thought this couldn't be simpler: ventilate, unhook the battery, connect the positive first, then the negative, then turn on the ...
10
votes
4answers
9k views

How do I apply dielectric grease to my battery?

I recently had a new battery installed in my 2006 Subaru Forester. The shop did not use any dielectric grease, just connected the leads to the terminal and that's it. What is the preferred method of ...
10
votes
2answers
830 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 ...
10
votes
1answer
70 views

Do any car batteries come dry with the electrolyte in a seperate container?

Small batteries for Motorcycles and Lawn Tractors are typically sold with the electrolyte in a separate bottle and must be added to the battery at home before installing it. I've never seen a "dry" ...
9
votes
2answers
136 views

Unknown part fell out of my motorcycle

So I was taking the battery out of my bike (99 Honda Shadow 750 ACE) to ship it this past December, when two parts of the bike I'd never seen fell out from somewhere near the battery case. They sort ...
9
votes
3answers
11k views

Using a car with an inaccessible negative battery terminal to jump start

When trying to jump start my Volvo XC-60, I came across a very unexpected problem. I tried to use our 2nd vehicle, a 2010 Ford Escape, as the assisting car to jump start mine. But when I looked at ...
9
votes
1answer
69 views

Replace car batteries with capacitors?

I recently watched this video on YouTube which basically shows the guy replacing a larger capacitors with some smaller capacitors which he had bought. The larger capacitors were actually in place of a ...
9
votes
1answer
175 views

Are there downsides to making an accessory socket always live, if accessories are removed when not in use?

In some cars, the power line from the battery to the accessory outlet (aka cigarette lighter socket) is always live. In others, it's off until ignition. It seems pretty much random which cars are ...
8
votes
4answers
64k views

What could cause my Honda Civic to not start? And how can I address the issue?

I need help trouble shooting my honda civic. It will not start. I was driving it earlier today and I went to drive it again when it would not start. I'm glad I was at home when it decided to quit. ...
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
2answers
5k views

Why might I experience a power falloff after starting my car with the AC On?

I have a 2000 Chrysler Neon which generally runs well. I have noticed that if I start the vehicle, turn the AC on and reverse out of the driveway, the engine seems to struggle/sounds like it is going ...
8
votes
6answers
21k views

2004 Ford Escape battery light comes on intermittently - what likely cause(s) are there?

I have a 2004 Ford Escape Limited on which the battery light has been coming on randomly for varying amounts of time while the vehicle is in active operation. I have checked the battery cables and ...
8
votes
2answers
36 views

Old starter clicked, wont turn over engine. New starter wont even click - no noise at all

My old starter would click, but not turn the engine over. I got a brand new starter and installed it. The only two wires connected to the starter are completely different and can only be fit in the ...
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 ...
8
votes
1answer
121 views

Does this crack in a battery terminal post indicate that the battery should be replaced?

Mechanics at the local garage have insisted it's "no problem yet", but people here in Sierra Leone have different standards to me when it comes to car safety... This is a pic of the positive terminal ...
8
votes
1answer
46 views

Disconnected wires near battery in BMW e46

I noticed a disconnected wire dangling next to the battery in the trunk of my 2005 BMW 330ci. It was actually a red and blue wire that veered off from the thick red one in the middle of the image. ...
8
votes
1answer
821 views

Remote Key Fob working only inside the car (close to reciever)

I am struggling to get my Peugeot 308 2-Button Remote Key back to work. I noticed first issues when my Remote Key unlocked / locked the car after several attempts. Then one day it suddenly did not ...
7
votes
8answers
4k views

Why use a car battery charger?

What's the need for car battery chargers that I often see on display in auto parts shops? I mean a battery is sold charged (and if it discharges too much it just dies and can't be restored) and every ...
7
votes
3answers
2k views

How should I prevent my battery going flat when I leave my car alone for a month?

I will be leaving my Focus alone for around a month in (scottish) winter weather. Ordinarily I would make sure to take the vehicle out at least once a week to prevent the battery going flat in the ...
7
votes
5answers
25k views

How do I know if my car battery is dead?

By mistake, I left the headlights on overnight for my Honda Civic 2008. 24 hours later when I tried to start it, the car would not start and nothing would come on including the internal lights and the ...
7
votes
4answers
443 views

Corrosion on battery, won't start, making clicking noise, won't charge

I'm trying to charge the battery on my 2002 Celica. Here is some background: Battery is a bit old, around 3 years or so. Corrosion has been building on the battery to the point that it almost ...
7
votes
4answers
4k views

Does turning off the radio and other electronics in a car before shutting off the engine prevent battery drain?

My father in law tells me if I leave the radio on in my car when I shut off the engine this will cause a bit of battery drain when I start the car. He says this will actually reduce the life of my ...
7
votes
1answer
340 views

Why the different the colors of terminal corrosion on the battery?

I have a 2001 Ford Windstar. When I went to clean the battery terminals: the one with the RED cover over it was a bright blue color; the other had normal white corrosion. I do not know why the this ...
7
votes
6answers
49k views

How many amps should my car pull while it is turned off?

I've recently started having a bit of trouble with my car. I typically drive my car to and from work each day. A couple weeks ago I went on vacation and when I returned, my car battery was as dead ...
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
2answers
89 views

Why do the batteries on some cars need to be hot-swapped?

By "hot-swap" I mean ensuring that the new battery is connected in parallel to the old battery while the old battery is removed and the new one is installed in its place. The idea is to ensure that ...
7
votes
1answer
308 views

Intermittent starting trouble with new battery

I sometimes have problems starting my 2003 Ford Fiesta Diesel. When I turn the key it'll either start normally or just start to kick over then die. If I try again, the same thing happens. My battery ...
7
votes
2answers
164 views

My car has problems starting, but the dealership checked the battery and said it was fine

I have a 2006 Toyota Rav4 - The other day, the car wouldn't start. We jumped the battery and it started right up. No lights were left on and nothing is plugged in that would be causing this. I took it ...
6
votes
5answers
246 views

Charging circuit

I have a motorhome and tow my car behind. Since I have to leave the car in accessory mode so the steering wheel is unlocked, the battery doesn't last a long time. I want to run a DS line from the ...
6
votes
1answer
861 views

Car Battery Dying Overnight - Disconnected

I have been having trouble starting my car (needed to jump it twice, once in the morning, and once in the afternoon). Sometimes it would make a clicking noise when trying to start or it would be ...
6
votes
2answers
7k views

How do you remove or even get to the car battery on a 2012 Honda Odyssey?

Summary How do you get to the battery on a 2012 Honda Odyssey, given that it is blocked by some type of intake tube**? **Edit: this used to say exhaust but I changed it to intake tube, given ...
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
576 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
3k views

What current is “normal” for constant battery drain (not parasitic)

I'm having some problems with battery going dead sometimes, and I noticed that there are some small sparks after disconnecting the battery for a few seconds and then reconnecting again. It is not big ...
6
votes
1answer
44 views

How can I dispose of the waste products I get from working on my car more effectively?

I have some real challenges disposing of various fluids and consumable objects from working on vehicles at home in my small workshop. Some of the more common things that I want to be able to dispose ...
6
votes
2answers
66 views

Car battery appears good but car won't start

My 2005 Nissan won't start today. Battery is relatively new(about one year old) and I can turn the lights on, front headlights, and it appears fine. However, when I tried to start the car by turning ...
6
votes
1answer
54 views

hooking up a battery tender to your car for the winter

Do I need to disconnect my battery to use a battery tender for the winter? Is there the possibility of damaging the charging system if I leave the cables connected? Thanks
6
votes
1answer
750 views

Battery voltage slightly low. Especially when the car's been sitting for a while

My car is a 2004 Mazda 3. This happened with the last battery I had as well as this newer one. Basically if I leave the car sitting for 2-3 days without driving it, it doesn't have the voltage to ...
6
votes
1answer
53 views

Help with Strange Intermittent yet predictable parasitic battery drain?

I'm having an issue where while testing circuits for the offending drain, I will see NO drain for about 30 seconds and then a 6-9 amp drain for about 10; rinse and repeat. Anybody have an idea what ...