How To Disconnect Car Battery

Be careful; it's small but dense, so lift with your legs, not your back. Make sure your engine is off. Be sure you pull both fuses. If you let your vehicle sit on the street or in a garage for an extended period, you may return to a dead battery or worse problems. V2 is the voltage across the ECU with the negative battery terminal disconnected whilst welding. Be careful because these batteries are deceptively heavy. First of all, it's important to remember that working on and even just disconnecting a car battery can be dangerous. The car wouldn't start and was towed to a repair shop. How To Disconnect A Car Battery Safely. Car battery trickle chargers slowly recharge your vehicles battery and are invaluable to have. Do this with a spanner by removing the negative terminal first (which is anchored to the black cable) and then the positive terminal (red). Keeping this mind, here's how to safely use a car battery charger:. I haven't done it before but I'm supposed to disconnect the negative and then positive right?. Give your ride a good handwash, polish up that chrome and apply a coat of wax to the paint. Audi Q7 How to Replace Battery Replacing a car battery is a job that is so easy, there's no reason to pay a dealership or mechanic to do it for you. This article applies to the Audi Q7. It resulted in one extra hour to get the Audi to 100%. More important than loosing the clock and radio settings, a '97 is an OBD II engine computer. Remove the Old Battery and Install the New One: Locate the battery - The battery should be located in an accessible part on either side of the car's frame. Disconnect the negative and leave the positive connected. Refer to your car owner's manual for a fuse box diagram, locate the position of the car alarm fuse, and pluck that fuse out using the tweezer-like tool in your fuse box. If your car battery keeps dying over and over again, one of the simplest explanations is that there is some kind of drain on the system that persists after you remove the keys and lock the doors. You’ve relocated the battery to the trunk, but having a disconnect at the track is a good idea anyway, as accidents can happen. Audi Q7: How to Replace Battery. Lift the Terminal Covers. A kill switch protects your vehicle from theft by completely disconnecting it from the battery or otherwise interrupting the combustion system that starts your ride and keeps it moving forward, which prevents the engine from starting and therefore stopping anyone who'd otherwise try to drive away with your car or truck in their tracks. The mechanics said all they did was remove and replace the battery cables. Or in the trunk, next to the spare tire. Lexus Remote Key Fob Battery replacement video. Disconnect the battery then unscrew the brackets holding it in its tray. In some cars, it is openly visible just after opening the hood while in others it might be hidden under a plastic plate. If you have some decent car wiring experience, not hard to find said device (follow all the wires) and route around it, but if you don't - better to find a friend or local shop that has a clue. These batteries are designed to last for many years but they aren’t as energy dense as the lithium. Knowing how to remove battery acid will help you move quickly and may prevent the battery from corroding. Materials Needed. Locate battery. Is this to be expected, and what can I do to ‘mend -it’ and restore The batery to its normal state ? The battery is just over 1 year (13 months) old. Both in my boat and 5th wheel. I recently replaced the oxygen sensor on my 2001 Corolla due to the check engine light. It can be left connected for an indefinite period, ensuring your car battery remains fully charged while you are away. Step 6: Disconnect the positive connector Loosen the nut on the positive terminal and disconnect it from the battery. If your car has a positive ground, you would loosen the positive cable first (your manual will tell you which your car has and the correct order for removing battery cables). You go to turn your ignition, and nothing happens. You just have to disconnect the terminals in the right order, unscrew the nuts and bracket that hold the battery to the plate, and you're all set. Guess God had other plans and after two more hours later the extra keys turned up. Toyota's stock battery is a Panasonic Group 35 battery. Wear eye protection when working with the battery to protect your eyes from sparks. In other words, be very careful while removing the battery. Make sure there are no foreign objects in the tray that could damage the battery. Remove the battery, being careful not to let the positive terminal touch any metal part of the car. If you are looking for Disconnect Volvo Car Battery, you've come to the right place. How to Remove Car Battery Terminals. Battery corrosion can also lead to a myriad of other car battery problems, including damage to the vehicle chassis, electrical wiring, air conditioner lines and more. Don't Miss How To Buy A Car Battery - Buying Guide. Battery cables screwed tight to the battery posts require an expandable wrench or screwdriver to remove. If it's a MkV or later, you'll want to lock the doors before you disconnect the battery, as the door locks can't be operated manually – there should be a hidden keyhole in the driver's door that you can use to unlock the car when you get back. Were here to ensure you get the very best price for your unwanted car. Will disconnecting the battery reset the airbag light or do I have to use a scanner?. 4 Mark the starter electrical wires for installation reference. These are handy to use, but if the battery dies you may find yourself locked out of your car. That’s it!. How to Remove a Battery in a Chrysler 300M Car batteries provide the electric current to start the engine and power the electrical appliances in the car. Even now with the car mended, and NO CEL's at all, I've had the battery out a few times and if I don't allow the car to re-learn to idle, I can feel the difference in the car. 18 hours ago · Buy Car Boat RV 300A Battery Master Disconnect Rotary Cut Off Isolator Switch with fast shipping and top-rated customer service. If it does, use an adjustable wrench to first loosen the nut and bolt on the clamp that holds the battery cable on the negative terminal. While the actual process to remove a car battery is fairly straightforward, there are other things you can do to ensure your safety as well as some general tips to keep in mind: Tip 1: Use zip. We show you how to change a car battery in this article. Charging a dead battery with an excessively high voltage can increase the off-gassing of hydrogen, which can, in turn, result in a hazardous situation where the battery might explode. So you have to know how to jump start a car safely and properly, so that when/if you ever do run into a dead battery in your car you can get back on the road quickly. But if you’ve got to do it, you might as well do it right and do it fast. If you let your vehicle sit on the street or in a garage for an extended period, you may return to a dead battery or worse problems. It’s a novice carpenter’s worst nightmare: you’re trying to tighten or remove a screw, and you find the head is stripped. How to Replace a Reverse Light Before you kick your car into reverse, make sure your reverse lights are working properly. Now, unscrew the hold-down mechanism to remove the battery from the tray. to see if the behavior goes away. My rv is stored for a couple of months at a time. For one thing, any house hoping to use power from the car in its driveway must be able to disconnect from the grid, which requires specialized. Check for this code in your owners manual - it will usually be either a sticker or small card in the booklet. With a 10mm socket wrench undo the negative terminal, and remove it from the battery. If you suspect this is killing your battery during storage, you can either disconnect the battery, or remove the battery from the car entirely. So it's important to know how to test a car battery. For safety reasons, battery cut-off switches are a valuable—and sometimes mandated—resource. There may come a time, however, when you will need to remove and replace it. There you will need to find the fuse for the car alarm. Drive the good car up to your car so the car batteries are as close as possible. A healthy battery will show 12. Locating the battery. Follow these essential steps and your car will be ready to roll. At least the battery would be topped up? Only to be told by the Audi rep that I used the wrong plug and I should remove the flap from the bottom part of the charger to allow for the fast charging socket. We'll even take care of the old one with battery recycling. Disconnecting the battery when a vehicle isn't in use can prevent your battery from draining while it sits idle for weeks or months. I was away on holiday for 5 weeks and had left my battery on charger during that time. Unhook the battery terminals. Disconnect the negative terminal first before the positive terminal. Insulated work gloves; Ratchet extender (if needed) Pliers or adjustable wrench (if necessary to remove a bracket holding the battery in place) Safety goggles. If you notice signs of damage or a low charge, the time is near. Auto Car Battery Disconnect Safety Kill Cut-off Switch Terminals Cut Off 6v12v. Charging your battery with a four amp charger will take about 12 hours to get a full charge out of this low amperage. These plates either clamp the battery to the tray at the bottom or sometimes over the top. Where is my car battery ? Here is a typical layout, highlighting the car battery and battery clamp along with the red and black battery terminals. Physically inspect for leakage or damaged cases, remove any corrosion, clean and dry the tops of the batteries to remove possible discharge paths from dried battery electrolyte, and clean the terminals. Remove the negative clamp from the ground point, and then the negative terminal on the donor car. Six CD changer will not accept or eject, mechanism seems jammed, will not play CD's. Wait the amount of time indicated by the manual for the type of charger you have and the voltage selected. With the old battery out, set it next to the new one and confirm that they are the same size and grouping. For concealed installations, where battery box space is limited, or in space restricted areas. Remove both battery cables (positive and negative) and then connect them together. Take off your rings and watches! Jewelry can play a surprisingly terrible role with electricity when your working on a car. Hi Guys, Battery ran flat in my BMW x 5 4. (It's usually black, and the corresponding terminal on the battery is normally marked with a "-" sign). In fact, under certain conditions a car battery may explode while just sitting in a parked car or on a table [source: battery-chargers]. Car Battery - Disconnect Most people do not realize that disconnecting a car battery for any reason may cause problems. But before that you must know this you can save up to $10 to $50, (₹600 and ₹1500 if you stay in India) on this Simple Battery-connecting task which would take at least 20 minutes. Audi Q7 How to Replace Battery Replacing a car battery is a job that is so easy, there's no reason to pay a dealership or mechanic to do it for you. The mechanics said all they did was remove and replace the battery cables. If something goes wrong, however, a dead battery can be impossible to ignore. I called aaa and had them come jump start. Step 3 — Disconnect the Battery. Open the hood and place a blanket or pad over the fender. Remove the battery cables from the battery terminals by loosening the nut on each cable clamp. Steps (and helpful tips) to Replacing the Battery in your MK6 (MKVI) VW GTI. Place your batteries on a shelf or piece of wood. Try starting your car. How to disconnect a car battery without losing memory You will need an extra battery and a set of jumper cables if you want to disconnect your car battery without losing memory. If you start with the positive terminal, you may short circuit it and this can be dangerous for you and the (expensive) electronic component of your car. Set it aside, away from the battery. Now that the secondary power is all set up, it's time to safely remove the battery. It is important to disconnect the negative lead first to prevent electrical shock, and reconnect it last. Nearly every car built in the past few years uses a keyless remote to lock and unlock the vehicle. At least the battery would be topped up? Only to be told by the Audi rep that I used the wrong plug and I should remove the flap from the bottom part of the charger to allow for the fast charging socket. Remove the Battery. When a damaged vehicle enters a collision repair facility, many times the repairs require the battery to be disconnected. Connect it up then take of the jump leads. There will be 2 or more fuses located on these wires, you just need to remove the fuses. The battery location will be under the hood in most cases but some cars may have it in the trunk or under the rear seat. How to Remove Car Battery Terminals. You press the screwdriver or drill bit into the head and try to turn. Removing the battery from the circuit allows those spikes and transients to travel around, endangering every semiconductor circuit in your car. Sears is having a 25% off sale on die hard batteries, my car is over 5 years old now and still on the original battery. Depending on the car you may have to relearn several things from radio presets to auto windows. 7 volts across both terminals when measured with a voltmeter, a simple device that's very handy when diagnosing battery issues. com article we'll explain how to disconnect a car battery. Remove the battery clamp and set it. When the car is off, the battery is not being recharged. The radio is definitely turned off when the car is off. While the car's ignition is off, the battery can still produce an electrical charge (and even an explosion) while the terminals are connected. Or in the trunk, next to the spare tire. I never heard of battery lasting this long that's why I typed this in computer to see if other people ever had one last this long. This guide will explain how to safely jump start a discharged car battery. Your car's manual, as a backside covering excercise will say disconnect the battery - maybe a result of garages being able to use high current, high voltage fast chargers, but for a more normal modern charger with a carefully controleed output, there is no need to disconnect. Take the wrench and pliers to the black (negative) connection or post and loosen same. Car battery trickle chargers slowly recharge your vehicles battery and are invaluable to have. Next, it needs to be at the 'rearmost' of the car. The car battery is an essential component which helps to start the engine and power all the electrical modules in the car. Disconnect the Battery. Never dead again: Boost your smartphone battery life—whether it's an iPhone or Android—with these easy tips you probably never knew about. Welding Circuit. Guys anyone with an idea of how to disconnect a GT battery without setting off the factory alarm. Disconnect the battery. To remove the side terminals, turn off the ignition and permanently remove 2. Physically inspect for leakage or damaged cases, remove any corrosion, clean and dry the tops of the batteries to remove possible discharge paths from dried battery electrolyte, and clean the terminals. To check the battery, you'll need to remove it from your vehicle. You will not loose your radio, seat, alarm or mirror settings as this unit comes with all you need to keep the memory and save your vehicles battery. If the headlights are overly dim, put the vehicle in neutral or park if automatic, and rev the engine. Best Answer: You only need to disconnect one terminal of the battery to minimize battery drain while you are gone. The dangers of boosting a car battery. Tips for replacing a car battery Here at Glendale Nissan, we can help get you the correct battery for any vehicle, from current models like the 2018 Nissan Rogue , to much older model years. Cleaning and servicing the car battery terminals is highly recommended and now that you are aware of how to disconnect car battery easily, you will have no difficulty in cleaning your car’s battery terminals. (2) Do not place your battery directly on the ground or floor. If the nut is rusty then apply some WD40 to help remove the nut. car battery, car maintenance, disconnect battery, positive negative terminals When carrying out any electrical work to your car, it is usually necessary to disconnect the battery first. But does your teen driver know how to use jumper cables safely? First, make sure it's the battery. The battery should now be free to be removed from the battery tray. Pull up and remove the top battery cover. Also Read: How to Clean Car Battery Terminals. Follow these tips to keep your battery—and your hands—in tip-top shape. ) and generally use lead-acid chemistry. The electric-car tax credit is supposed to incentive and help offset the purchase of battery-electric cars and plug-in hybrid vehicles. Take the wrench and pliers to the black (negative) connection or post and loosen same. The car wouldn't start and was towed to a repair shop. Some Honda models may have a second bracket that surrounds the battery. Remove the bar that blocks the battery and be sure to set it aside in a safe place where you’ll have easy access to it. The city wants to remove 100 parking spots to make way for charging stations for electric cars — even though they make up just 0. As with traditional gasoline power trains, you must disconnect the vehicle's battery before attempting mechanical or electrical repairs. Where is my car battery ? Here is a typical layout, highlighting the car battery and battery clamp along with the red and black battery terminals. Here's how to remove a car's engine and transmission. Remove the positive cable (typically red) from the positive terminal (marked with a “+” sign) of the booster car battery. Remove the cushion from the car. It seems my battery is almost dead and I am not waiting around for Ford Care to tell me I need to pay for a replacement when I can change it myself if only I could disarm the Alarm and get the old one out. The battery should now be free to be removed from the battery tray. Even if you've already ruled out obvious things like the headlights and dome light, there may still be a drain in your system. Connect it up then take of the jump leads. Here's how to remove a car's engine and transmission. 5 Note the routing of each cable. I used to disconnect my car's battery and leave it for months, then I'd come back and it would be running smoothly from the first second. I just got my new 109 relay the other day, when I went to install it, I opted to disconnect the negative terminal of the batteryswapped the relay, buttoned up the fuse panel, went to connect the battery, and the alarm starts going offI didn't know the car had an alarm!. Remove the screws or fasteners holding the battery in place; then Remove the Battery. If you switch this order, nothing bad will happen — if you don't make contact between the positive side of the circuit and the ground. In any case, to remove the battery, disconnect the positive (+) cable, then disconnect the ground (-) cable. With the old battery out, set it next to the new one and confirm that they are the same size and grouping. How to Remove Car Battery Terminals. These are handy to use, but if the battery dies you may find yourself locked out of your car. This is permanently installed on the battery cable and terminal and allows you to easily disconnect the battery cable each time you want to tow. While the car's ignition is off, the battery can still produce an electrical charge (and even an explosion) while the terminals are connected. The Final Detail. To access this list, head to Settings > System > Battery > Battery Usage By App. Reconnect the battery cables, pos first and then the neg. After disconnecting the battery from motherboard, slightly bend the bottom cover to release the tabs. To remove the cables, reverse the order in Step 2. Step 6: Disconnect the positive connector Loosen the nut on the positive terminal and disconnect it from the battery. Audi Q7: How to Replace Battery. In some vehicles, the battery can be found underneath the rear passenger seat or in the trunk. It is critical to disconnect a negative battery terminal before starting any work on your car - any car manual or auto mechanic will tell you that. This my first time removing an engine from a car. Once you’ve completely disconnected the battery, unscrew the bolts holding it onto the battery tray. Turn the charger off and unplug it before removing it. It's the only way to prevent. Keep the cables away from the battery terminals (using a bungee, you can "hang" them from the open hood as an option) and let them remain connected for at least half an hour. Knowing how to remove battery acid will help you move quickly and may prevent the battery from corroding. With a little knowledge and caution, you too can replace the battery in a matter of minutes. To access the battery you may need to remove the plastic cover. And I wouldn't bother keeping it on the charger for eight months -- you'd just be wasting electricity. In fact, under certain conditions a car battery may explode while just sitting in a parked car or on a table [source: battery-chargers]. Wear eye protection when working with the battery to protect your eyes from sparks. Year on year, car battery problems are one of the top reasons for roadside assistance calls. The car wouldn't start and was towed to a repair shop. Always exercise caution when handling any electrically charged component. If your car battery keeps dying over and over again, one of the simplest explanations is that there is some kind of drain on the system that persists after you remove the keys and lock the doors. I was always told to disconnect the battery from the car by at least the neg lead while charging. Well, you can easily disconnect or remove a car battery in that situation. If the stains are only on the surface and have not eaten through the fabric, you may be able to remove them with ammonia. Remove the terminal from the battery post with a twisting motion. Keep track of your battery's life and replace it before it leaves you stranded. The battery is in the right side rear of the trunk. How to reset the Computer code after disconnect / replace the battery 22 Answers. To ensure that you unhook the battery the safer way, you need to follow the following steps: 1. For concealed installations, where battery box space is limited, or in space restricted areas. Disconnect the negative battery cable, wrap the cable end with a shop towel and place it away from the battery post. The final step is to again remove the caps from the battery and attach it to the battery charger for 24 hours. The terminals on your car battery are an essential component for the function and life of your engine. This my first time removing an engine from a car. The main reasons to remove the battery are to change or charge it. Subject: battery safety. (1) If you store your boat in a region with cold winters, remove your battery and store at home in a dry location. Locate and remove the 10mm bolt at the center passenger's left hip. Disconnect batteries quickly and easily. The negative battery cable is the one that has black insulation on the wiring. Disconnect the Battery. (audio doesnt even work period) i know the fix is to disconnect and reconnect the battery, im mostly interested in knowing whether you can be shocked disconnecting using a metal wrench. 5 volts, I’m guessing sulfation is already occurring at this voltage…. Battery Disconnect Switches Battery disconnect switches give you the ability to cut power to your ride before storing your hot rod battery during routine maintenance or after an on-track accident. Worst case, yank the brain (usually the harness has a disconnect on it, makes it easier to install) and see what happens. Disconnect the positive terminal. Disconnect the battery charger – first remove the negative clamp from the battery, and then remove the positive clamp. Disconnect the negative cable from the engine block or other ground location. It was an amazing learning experience, and I did (most) of it myself! I documented some of the major steps in the video below: The engine and transmission were removed from my 2001 Toyota Corolla. A trickle charger, sometimes called a battery maintainer charger will keep the battery in good shape without having to disconnect it. We disconnected and reconnected the battery and guess what - the car started. 5 volts, I’m guessing sulfation is already occurring at this voltage…. The first step is to remove the old battery. remove the old battery and install the new battery Locate the battery - The battery should be located in an accessible part on either side of the vehicle's frame. Remove the screws or fasteners holding the battery in place; then Remove the Battery. Normally I would remove it (last car was a Montego) but with these new fangled jobbies (Mondeo) I've heard that disconnecting the battery can play havoc with the computers/radio etc. On my return, my battery has , for 2 rounds of golf, failed to recharge when put back onto the charger. if your doors are open when you reconnect the battery the alarm will sound, usually sending your head into the hood, and the hood back down on top of your head. We'll even take care of the old one with battery recycling. Battery Disconnect Switches Battery disconnect switches give you the ability to cut power to your ride before storing your hot rod battery during routine maintenance or after an on-track accident. Depending on the model it is either on the engine bay, typically on the passenger side. If the car is going to be stored and won't be used at all for a few months, you could disconnect the battery negative cable, says Stephen Leroux, professor at Centennial College in Toronto. An electric device for that matter should be replaced, plus the cost of labour (about 2 hours according to the estimate). Disconnect the battery whenever you work on it, but be sure to shut the engine off first! On most modern vehicles, computers control functions of the engine, fuel and ignition systems, automatic transmissions, and other stuff. Determining the battery type. Always disconnect the negative post first, and in your case that's all you have to disconnect. Click to expand Even with my profession, and how many times this has happened, I still jump when this happens to me on a customers car. I need to swap out the alternator on my 2011 MB GL550 and want to know the simplest way to disconnect the battery? Is it by accessing the battery under the drivers seat or the terminals under the ho. Always remove the negative first, then the positive. Any group 35 battery will fit as long as the negative is on the left front. Remember to remove your car key from the ignition and shut off the car before performing this guide. After 2 or 3 more starts, the car wouldn't start again. 1 x Battery Disconnect Knife Blade. Place your batteries on a shelf or piece of wood. If your car battery keeps dying over and over again, one of the simplest explanations is that there is some kind of drain on the system that persists after you remove the keys and lock the doors. Clean cable ends - Clean the cable ends as needed with the wire brush and battery cleaner as needed to remove any corrosion. Leave enough space between the two so you can open both bonnets and get your jump leads between each car battery. We recommend changing the battery in Cadillacs every 4 years. Car battery chargers run off AC power and provide 12V DC at relatively low voltages, which is the best way to charge a completely dead battery. FACT: Almost 99 million wet-cell lead-acid car batteries are manufactured every year. Be careful; it's small but dense, so lift with your legs, not your back. Start the vehicle. Pull up and remove the top battery cover. Disconnect all add-on components wired directly to the battery or positive main engine block terminals. Next, cut off about 1/2 in. A car alternator needs to be putting out at least 13-14 volts (ideally between 13. Disconnect the negative and then the positive terminals from their respective posts. How to Safely Work on Hybrid Electric Vehicles. Easy-install battery disconnect has a removable knob that lets you disable the battery and prevent power drain. Disconnect the negative cable from the engine block or other ground location. It's the only way to prevent. For safety reasons, battery cut-off switches are a valuable—and sometimes mandated—resource. This device will broadcast that the vehicle has no battery power. However, you must be cautious because you will be working with dangerous chemicals. Remove the battery, being careful not to let the positive terminal touch any metal part of the car. Car batteries are heavy so lift the battery up, out of its tray with care Use diluted baking soda mixture with old toothbrush to brush the tray and connectors. We know, it's a pain! You'd like to pull it out and get it checked at an auto-parts store or maybe even replace it—and you want to do it yourself. if i don't drive the car for a week it won't start, but if i start it every couple of days it's fine. 8is after I left the key on about 4-5 hrs, some interior lights were on and CD Player was on. car battery, car maintenance, disconnect battery, positive negative terminals When carrying out any electrical work to your car, it is usually necessary to disconnect the battery first. Then, disconnect the main engine cable connection to the electrical block. You just have to disconnect the terminals in the right order, unscrew the nuts and bracket that hold the battery to the plate, and you’re all set. The car battery is essential to sustain the functionality of the vehicle. Loosen the clamps or screws that connect the battery to the terminals and disconnect the securing mechanism that holds the battery in its housing. First, disconnect the battery cables starting with the ground terminal and then the positive terminal. Since a GPS locator is tiny, it's easier to set up but difficult to spot. Today, you risk frying every electrical device in your vehicle. By the time you are through with this article, you'll know the proper way to sever a battery connection without any mishaps. Follow these steps carefully. You will experience the difference when you use your reconditioned battery in your car. Your car's manual, as a backside covering excercise will say disconnect the battery - maybe a result of garages being able to use high current, high voltage fast chargers, but for a more normal modern charger with a carefully controleed output, there is no need to disconnect. Apparently, the question of how to remove car battery clamps and bolts in order to disconnect and lift out your old car battery has a few simple answers. I expect that it will loose its memory when you disconnect the battery, and have to 'relearn' its normal parameters every time you restart the car. Here’s how. If your battery is dying, or you are having issues getting your car. Do this with a spanner by removing the negative terminal first (which is anchored to the black cable) and then the positive terminal (red). Do it yourself guide to changing a dead battery in a Toyota Camry with step by step instructions on how to disconnect, remove and install a new 24F car battery. Beleiving in these myths can prevent you from taking proper care of your car battery, and as result, lead to shorter than normal battery lifetime. If you have a car alarm battery back-up alarm, then you may need to disconnect it before you can change either your car alarm, or the battery itself. I had some work done in my car which i had to disconnect the battery, just that uconnect will not work until i input the 4digit code which i cant find anywhere in the car vin: 988611156gk044870 radio s/no: 00268. Cleaning and servicing the car battery terminals is highly recommended and now that you are aware of how to disconnect car battery easily, you will have no difficulty in cleaning your car's battery terminals. It does this by tracking CPU usage over time, then listing which programs are using the most power. Whether it be for simple car repairs or a major engine repair, knowing how to disconnect your battery will prove to be an extremely valua. Luckily, it's pretty easy to jump your battery and bring it back to life with a few materials and a little basic know-how. Battery cables screwed tight to the battery posts require an expandable wrench or screwdriver to remove. Check the electrolyte level before recharging. Today, most cars have a single maintenance-free 12-volt acid battery (in the photo). 4 kWh representing a large difference in use of electricity in hybrid cars. But does your teen driver know how to use jumper cables safely? First, make sure it's the battery. *Warning* remove the negative cable off your car battery. Cut off power on racing cars & prevent fire. How to Test for a Bad Battery. Check mounting surface for objects or protrusions that could cause damage or wear to the case or cover. Make sure all of the accessories in the vehicle are off, to prevent arcing. i have a weird problem where my cars sterio system is on when my car is off and drains my battery.