How to fix a car battery that doesn't hold charge

Last updated on July 13th, 2023 at 05:06 pm

If your car battery is malfunctioning, it would be incapable of retaining charge. This would always give you a hard time getting your vehicle to start. Conversely, there are people who experience no form of difficulty in starting their vehicle because they have a sound battery. Luckily, there are ways to fix a car battery that doesn’t hold charge.

As a substitute for contacting your mechanic, you can do this yourself at home using some tools.

So when you have fully charged your battery, the next line of thought is how long should car battery hold charge after is has fully been charged?

well, we start with that. Read related article on Electric Car Battery Lifespan and replacement cost.

How Long Should Car Battery Hold Charge

Usually, the average time a car battery sits or hold a charge is totally dependent on the kind of car. Most vehicles will hold charge 12weeks months before requiring a recharge.

You have to look out for the specific vehicle safe sitting time frame for car specification.

If you intend leaving your battery to sit for a long time without use, then I will recommend you get a battery tender to be a safe side. Then remove the battery and store with the tender outside of your vehicle. This will help preserve them longer. you might want to read this article on 10 Best Battery Tenders for Cars (Your Ultimate Guide) to help you make the right choice of a tender to go for.

How To Fix A Car Battery That Doesn’t Hold Charge

To fix a car battery that doesn’t hold charge you’ll need some basic requirements:

Items needed

Protective eyewear
Plastic funnel
Battery hydrometer
Battery post/terminal cleaner
Screwdriver
Voltmeter with probes
Battery load tester
Battery treatment (optional)
6/12-volt battery charger/starter

So, let’s look at how to fix a car battery that doesn’t hold charge by following the 5 steps below.

#1. Prepare the battery

Put on protection specs and clean the battery posts. Battery posts can be tidied by inserting a battery post cleaner on every battery post and using a back and forth motion to turn it back until the posts are clean.

#2. Perform a load test

To perform this test, start by linking the load tester to the positive terminal before connecting to the negative. This is essential in a bid to avert sparking issues. Turn on the load tester to confirm if the meter dropped. If the meter falls to the base of the scale and stays there, it means the battery is completely dead, and necessitates a replacement.

#3. Take out the cell covers

To do this, place a screwdriver beneath the rim of the cell lid and lightly pry it up. Take away the cover and place it to one side.

#4. Carryout a hydrometer test

You can perform this by squeezing the bulb and inserting the tube into a battery cell using the hydrometer. Press the bulb severally to stir up the battery fluid. A dark-coloured liquid signifies a faulty cell that requires replacement.

Furthermore, you can draw the juice up into the scale portion of the hydrometer by compressing the bulb and releasing it while the tube is in the fluid. Note down of the color the fluid rises to.

Green indicates a good and strong battery
Red color indicates the battery has to be recharged
White signifies a fair battery

Be certain that the lead in all cells is submerged by the battery fluid to least 1/8 inch. Repeat same test on all cells noting down the evaluations.

Wheels Bearing Replacement Cost (Ultimate Guide for Different Cars)

#5. Test the cells

Position the positive voltmeter probe on the positive battery post and the negative probe in the first cell. The cell should at least two volts on the meter. If this isn’t the case, then it means there is a problem with that cell. Next place the positive probe in the first cell and the negative probe in the second cell. Then place the positive probe in the second cell and the negative probe in the third cell. Keep doing this until all the cells have been tested and the readings have been noted. The final reading should record zero.

Alternatively, you can add the treatment chemicals if you wish. This is to service the battery and clean the cells. You have to abide by the instructions on the label when using the chemical. Pour the chemicals into the cells. Return back the cell covers and position the battery on “trickle” charger for at least 24 hours. The most excellent way to repair a battery that will not retain charge is to use a trickle charger. A battery that has been run low constantly requires a slow-charge for 24 hours.

Caution

Ensure you always fasten the positive cable up first and take it out last to prevent lethal sparking.

e. Car battery not charging with charger

If your car is unable to start or giving hard starting, the first thing you’ll probably suspect is a battery fault. Nevertheless, it isn’t every time the fault could be a poor battery, it could also point to another problem. A faulty alternator, clogged fuel filter, or faulty injections can all cause a car battery not to start.

Normally, the battery of your vehicle will go through loads of charges and discharges during its life span. It is essential for the battery to be recharged while the engine is running. This is to prepare it in support of the next start.

The problem may not always be the battery, but it can result from a battery not being properly charged by the charger.

How Car Battery Charges

Though automobiles have undergone drastic changes in designs and assembly, however, the charging of the battery still remains fixed over the years.

Normally, the starter motor is power-driven by the battery to start the engine when the key is turned in the ignition.

This process gives the initial spark to the spark plugs of a vehicle. The alternator recharges the battery once the engine has started.

When the engine begins rotating, the alternator is driven by a belt that changes mechanical energy to electrical power, hence supplying power that is used to charge the battery. A charged battery supplies power to other parts of the vehicle.

A car battery not charging with the charger could be caused by several factors.

7 Reasons Car Battery Is Not Charging with Charger

So sometimes you might notice that car battery not charging while driving and there are a couple of reason that is so. On other occasions you see that your car battery always needs to be jump-started severally before it starts, then there are ways you can diagnose the fault and rectify the issue. And blow are then ways to do just that.

1. Check battery terminals for improper connections

Checking the terminals and wirings for poor connections may be tasking on current vehicles where batteries are integrated into tight compartments. This may require you to take out some plastic covers before getting the battery out.

For older vehicles, the battery terminals may have become mouldy or may have slackened. You can wash up corroded terminals with a wire brush or sand-paper. It’s not likely that the wiring has to turn out to be damaged as it’s usually somewhat protected.

2. Check the car battery condition

After jump-starting the car, allow it to remain attached to the donor car for a few minutes so as to allow the battery chance to charge. The fault may be from the battery of your vehicle not charging if the car stops when the jump cables are pulled out.
Ensure you put off other accessories that may drain the battery, also take out the keys from the ignition too.
Then proceed to set the DC current making use of a basic voltmeter/multimeter set to DC current.
Join the +ive lead to the +ive (red) battery terminal. Attach the -ive lead to the -ive (brown or black) terminal.
The reading should be 12.5 Volts, plus or minus 0.2 Volts when the engine is off. A lower voltage indicates the battery isn’t properly charged. This could point to an alternator issue.

3. Check the alternator for defective alternator

If the battery appears to be fine, then a defective alternator may be the reason why your battery isn’t charging with the charger.

Some symptoms of a damaged alternator may include:

Dimming headlights
Car unable to start
Charging warning light appearing on dashboard

To test out an alternator, with the engine running, join the voltmeter. The reading is supposed to fall between 14v and15v. If this isn’t the position, then there is the inadequate electrical energy to power the battery.

Examine the alternator and check for any wiring problems. This may call for the services of an experienced auto-mechanic.

4. Check aftermarket devices for unrestrained drain on battery

An automobile with an after-market security system or radio may be responsible for draining the battery. This is habitually complicated to decipher. Most after-market devices should totally shut down when the engine is off. Some may require a stable live coupled so that they can keep hold of some settings.

5. Run a diagnostic to check for error codes

All cars have numerous ECUs that deal with lots of electrical systems that are vital for running the car. If one of these control units is defective, then it can lead to a battery problem.

A diagnostic scanner should be able to deduce any fault codes that have been documented by the ECUs. You can contact a mechanic or get a scanner to check it.

6. Check drive belts and pulleys for damaged drive belt

The alternator is being driven by a rubber drive belt. The speed of the alternator is proportional to the engine speed.

In some cases, the belt can broaden or become worn, particularly in older vehicles. This can make it slacken its hold on the alternator pulley making it to slide. A slacken belt will be unable to drive the alternator fast enough to produce power for the automobile. A slipping belt could cause noise to emanate from the pulleys, thereby necessitating replacement.

7. Check fuse box for blown fuse

Cases of blown fuses are common in older vehicles. It could be old age has caused them to become fragile and worn out. To rectify this issue, check the fuse for the starter motor and the alternator.

Also, verify the user instruction manual for more details about the position of the fuse box.

Conclusion

If you fail to notice any issues yet the car battery isn’t charging with charger, then you may need to consult your auto mechanic or auto-electrician.

In some cases, where a battery isn’t the quandary, a faulty alternator may be responsible for a car battery not charging with charger. If the alternator is confirmed to be in perfect shape, then there may not be sufficient power to charge the battery. It is still best to confer with your mechanic if you are incapable of rectifying the problem.

how long does it take to fully charge a tesla+ Tesla Battery Replacement Cost

Wheels Bearing Replacement Cost (Ultimate Guide for Different Cars)

Are Burnouts Illegal: How to Do a Burnout In An Automatic BMW