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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21
votes
4answers
4k 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 ...
18
votes
9answers
49k 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 While they have all been replaced by warranties, it'd be nice to get the problem solved permanently.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 ...
8
votes
2answers
3k views

Why should I connect the red/positive terminal first when jump starting?

So, it's fairly popular consensus online that it's red/positive clips to the positive/red posts, then the black/negative clip to the frame One site mentions sparks, but you'll still get a spark when ...
28
votes
3answers
11k 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 ...
2
votes
4answers
1k views

how much water can be safely added to a battery?

My 2008 Jetta SE 2.5L has the battery as follows: ENERTEC EMC // 1J0 915 105 AD // 12V 61 Ah 330A DIN // 540A EN/SAE. It would appear that the battery can no longer hold the starting charge after an ...
21
votes
6answers
25k 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 ...
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
318 views

Battery Light Won't Go Off Since Changing Battery

I just changed the battery on my 98 Mazda 626 and now the battery light comes on and stays on after starting the car. I checked the battery and it's reading 12.8v with the engine off, and 13.8 with ...
3
votes
4answers
16k views

Should I use coca cola or baking soda + water to clean my battery clamps?

The clamps that are attached to the car battery are corroded, I was told either of these liquids will work. Which one is better? Is there a how to guide on the exact steps I need to take? With my ...
2
votes
1answer
322 views

How do I add an auxiliary battery to a van?

I have a 2500 Savanna (GMC, 2001, extended), with an entertainment system. The stock battery is fairly small, and I don't want to run the engine or drain the engine battery when playing videos for ...
16
votes
5answers
11k 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 ...
4
votes
2answers
5k views

What is the difference between a normal battery and a maintenance free battery in a 2 wheeler segment

What is the difference between a normal battery and maintenance free battery. Is a maintenance free battery really free of maintenance or just it requires less no of charge cycles. I currently own a ...
3
votes
3answers
4k views

Getting information from manufacturing code on Exide car battery

If you can help me decode the following manufacturing code on EXIDE EA640 battery, especially which production plant has made it what was the date of manufacturing Code: 3EC28K5 Perhaps 28K ...
50
votes
6answers
3k 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 ...
34
votes
3answers
34k 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 ...
5
votes
4answers
30k views

What precautions are needed when charging a car battery in an apartment?

Suppose a car owner lives in an apartment building and parks his car nearby. He wants to detach the battery, bring it home and charge it with a mains-powered charger indoors. How to properly handle ...
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 ...
6
votes
1answer
114 views

Starting using a deep-cycle battery

This weekend, during a camping trip, the starter battery on my 2001 VW Eurovan camper started to show signs of weakness - cranking was much slower than usual and took about 5 attempts to get the ...
6
votes
1answer
5k views

How to track down an intermittent battery drain?

I know there are several questions on here about finding the source of a battery drain (like Battery drains by itself when vehicle is parked (parasitic draw) ). However I don't think the answers ...
14
votes
5answers
76k 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 ...
13
votes
1answer
301 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 ...
10
votes
4answers
10k 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
1answer
227 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 ...
6
votes
1answer
201 views

how do i know if my lead-acid battery has been resurrected?

The OEM battery in my 2008 Jetta SE 2.5L has been nearly fully discharged one month back (had insufficient surface charge after a prolonged use without the engine running, but leaving it idle for 20 ...
5
votes
2answers
469 views

Car battery won't charge above 50%

I had a problem starting my car after not driving it for two weeks. After charging the battery with a CTEK trickle charger via the cigarette lighter socket, the car started fine. I had my car battery ...
5
votes
4answers
1k views

Is it recommended/necessary to wear rubber gloves while replacing a car battery?

I'm not too car-savvy but I want to start working on my car on my own. My first challenge has arisen: replace battery. Do I need to concern myself with being shocked while trying to change the ...
4
votes
1answer
62 views

Poor battery condition, replacement required! Or is it?

I drive a 2004 VW Passat B5. Recently, my insurance company came round to fit a black box to my car as part of the terms and conditions of my car insurance policy. Whilst they were doing this they had ...
4
votes
3answers
963 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
4answers
73 views

Replace or recharge a battery after is has been drained?

The keys in my car were left in the on position for about 12 hours (and maybe the interior light left on) and the battery is drained. Is there any way I tell if I should replace the existing one or ...
3
votes
1answer
237 views

89 jeep cherokee will run but when i turn it off and try to restart it the battery is dead

The battery is still good and the motor will keep running when you disconnect a terminal. Can my alternator be bad? If not I'm also thinking a dead short? What is the best way to find out?
3
votes
2answers
177 views

Should i check quantity of battery liquid?

The battery of my Nissan Tiida is similar to the ones in the pictures below. Should I check if there is enough liquid inside? and in case it needs, should I add distilled water?
3
votes
0answers
47 views

Negative surface charge?

At about 20°C, there has been a situation that the OEM battery in my '08 Jetta was not capable of starting the car at all (virtually no movement of the starter at all), after being used for at ...
3
votes
2answers
2k views

would a sulfated discharged 12V battery charge at 12.5V?

I got a Stanley FATMAX RE-CHAGEiT 8AMP Automatic Battery Charger & Maintainer from Walmart for 29,97 USD, which appears to have three states of charging the battery -- detecting the voltage, rapid ...
2
votes
1answer
422 views

Power vampire in car. Where do I start looking?

I have been to the car store four times and each time they tell me that the battery is good. A few of the cold-cranking amps (maybe at 50 or so, I don't remember the exact amount) are gone otherwise ...
2
votes
3answers
30k views

The car makes clicking noise when i try to turn on the engine. What could be the problem?

I've a 2007 honda civic. The radio and everything work fine, but when i try to turn on the engine it makes clicking noise. I thought, it could be a battery problem. I also try jump starter to start ...
2
votes
2answers
452 views

when trying to start my pajero it just clicks and wont fire up

pajero wouldnt start and just clicks had aa out and they said it was the alternator but tried car over weekend and it started first time. tried this morning and just click had to have a jump start to ...
0
votes
1answer
101 views

Calculate car battery life using OBD parameters

I want to calculate the battery life of a car based upon OBD2 parameters like engine load, distance traveled, Control Module voltage etc. Can anyone please guide me as to how to do this? If ...