How to eliminate the Battery Discharge Warning in Your Car?

Battery Discharge Warning Batteries

Most modern vehicles often display a “Low Battery Warning” warning message.

This is the current state of your vehicle’s battery and a low battery warning does not mean you have a bad battery, but you still get discomfort when you see such a warning.

Battery Discharge Warning

Battery Discharge Warning

You can get this low battery warning if your car battery is constantly running low and it doesn’t matter if your car is on and charging.

Quick answer:

In most cases, restarting your car will charge your battery and reset the low battery warning message.

You can correct the low battery warning by turning the car on or turning off the stereo or other electronics you are currently using. You may also need to replace the car battery or find the underlying reason why you are getting this warning.

Why does this happen?

This occurs when the current in the battery is less than the current output. For example, you may get this message when you turn off the engine but keep the ignition on to listen to the radio.

You may also get this warning if your battery is old and no longer holds a charge, or on very cold winter days when battery performance decreases.

If you get a low battery message, you probably have a dead battery. The battery is low when you turn off the engine but do not turn off the lights, radio, heated seats, air conditioning, or any accessories.

A low battery warning also often appears in the winter if your battery is more than five years old.

This error message may also appear if the car has been parked for several days. If you leave your car parked for an extended period of time, use the battery to charge the battery.

In addition to the low battery warning, on some models, you may see “Low battery mode” “Low battery, soon to go into power saving mode” or “Safe power mode”.

The error message may still appear the next time you start the vehicle. Drive for at least 30 minutes and the error message should disappear. If it does not perform the troubleshooting steps below.

System Charging

If your vehicle has a charging problem, you will likely receive a safe charging stop or power system maintenance message. An urgent error message on the instrument cluster.

It could be related to:

  • bad alternator
  • bad battery
  • voltage regulator
  • the defective central electronic module

Low Battery Warning What’s the Cause?

Common Causes

Here’s a list of the most common problems that cause the car battery warning on the dashboard.

Battery life

If you have a battery that hasn’t been changed in over 7 years, the problem may be with the battery itself. With an old battery, you are more likely to get a battery warning in very cold weather. On rare occasions, cars with a battery that is only two years old have reported this problem.

Weak contact

A weak or corroded connection on the battery or at any point on the ground can cause a low battery warning.


The alternator may also be at fault here. If the alternator is not charging the car battery properly, the car battery will not charge when the warning message appears on the dashboard.

Voltage regulator

The alternator has a constant onboard voltage that helps keep the voltage in the 12.5-14 V range when the vehicle is in motion. Voltage regulators can fail, which in turn causes error codes such as stop charging or the power system.

Excessive battery discharge

Another problem that can cause battery warnings on cars is modules that draw current even when the car is off. For example, a satellite receiver may be drawing excessive power when the engine is off. Ask your dealer to diagnose the problem and, if necessary, update the satellite module software to correct the problem.

What should you do when you receive a battery warning?

Deciding what to do when a car battery warning appears can be tricky. If the problem is only related to a partially discharged battery, continuing to drive will help recharge the battery and the error message will disappear.

On the other hand, if the battery charging system isn’t working, you may drive another 10 or 20 minutes before your car stalls.

Here are a few actions you can take, especially if you receive a low battery warning.

Unplug your phone chargers

Make sure you remove all chargers from the cigarette lighter socket. Auxiliary outlets draw current from the battery. Plugging chargers and adapters into the cigarette lighter socket may cause excessive current draw from the battery, especially with the engine turned off.

Drive the vehicle for at least 30 minutes and see if the low battery message disappears. If the low battery message continues to appear, the vehicle battery may need to be replaced.

Charge the battery

If you get the low battery warning and you have a relatively new battery, try charging it. The best way to charge a car battery is to use a smart charger and connect it to the starting terminals from an external source.

Although it may take several hours to charge a car battery using a manual charger, this is the recommended method because it allows you to fully charge the battery. Follow these instructions to learn how to charge a car battery. You can also go on a long trip, and this will also allow you to fully charge the car battery.

Check the charging system

The easiest test you can do is to use a multimeter and check the voltage on the battery with the car running. The voltage should be in the range of 13 to 14.5 volts. To get a better idea of your car’s alternator and battery, perform a charging system test.

You can do this yourself, as it’s a simple test, but you’ll need a charging system analyzer. Follow this guide to learn how to check the charging system yourself. You can also visit your local parts store to have your charging system checked for free.

Updating the software

If your vehicle has more than one module. One or more modules in your vehicle may be drawing excessive current. For example, the vehicle’s satellite module has been known to draw excessive current.

Updating the software at your dealer may solve this problem. Call your dealer and ask if there are software updates for your specific car.

Why does the battery discharge to a critical level and how to avoid it?

In fact, discharging is the normal operating mode of this device, which has only two operating modes “discharge” and “charge”. Problems occur if the energy expended is not sufficiently replenished.

This occurs for two reasons:

  1. Electrical equipment malfunctions
  2. Operating errors

Why does the battery discharge quickly?

Physical wear and tear of the battery

Experts note that after 3-4 years of operation, the battery capacity decreases by 30-40% of the original indicator.

To slow down this process, you can use the following techniques:

  • Reduce the frequency of engine starts
  • Do 10 to 12 miles of driving to stabilize the electrolyte level
  • Charge the battery regularly with a working battery charger, as partial discharging increases the rate of sulfation.
  • Do not allow the battery to be deeply discharged
  • Regularly check the electrolyte level in the unit
  • At least once every 12 months to prevent sulfation of the plates.
  • However, if the battery is 3-4 years old, such manipulations may not give a positive result, since its resource is already exhausted

The generator does not provide charging

The procedure is carried out according to the following scheme:

  • First of all the engine is started
  • Turn on maximum power consumers at idle speed (car radio, headlights, seat heating, etc.)
  • Use a multimeter to measure the voltage across the battery terminals (the optimal value is 12.014.4 V)
  • If the meter shows a lower value, the battery will discharge faster. If the voltage is higher, it will begin the hydrolysis process whereby all the water in the electrolyte will quickly evaporate

If the alternator fails, it should be repaired as soon as possible.

Leaking Current

To see if the battery is rapidly dying due to current leakage, a universal multimeter should be used.

The test is carried out according to the following instructions:

  • first, remove the key from the ignition
  • then disconnect all electrical consumers from the on-board power system
  • then open the hood of the vehicle and remove the “minus” terminal from the battery
  • after that connect the socket on the multimeter to the disconnected battery terminal
  • start the device in the leakage current measurement mode (the optimal value is from 15.0 to 70 mA)

Loss of electrolyte efficiency rating

Excessively fast battery discharge can be caused by reduced electrolyte density and increased fluid evaporation. These problems can be solved, but only with proper and timely battery maintenance.

To check the electrolyte level, you can unscrew the filling plugs. The optimum level is slightly above the electrodes.

To measure the electrolyte density level, you can use an areometer. If the value is higher than normal, the electrolyte mixture should be diluted with distilled water.

If there is no loss of electrolyte, the battery is fully charged, but the density of the mixture is too low, it is necessary to take a rubber bulb with an extended tip to remedy the situation. A little of the old electrolyte is filled into it, and then the new electrolyte is poured in its place. It is necessary to stir until the density value reaches the normal value.

Driver forgetfulness

Sometimes motorists forget to turn off the electrical appliances in the car. These can be headlights, windows, interior lights, etc. Experts do not give any recommendations in this regard. However, car manufacturers are already trying to solve such problems by equipping the car with automatic shutdown of electronics after some time after engine shutdown.

Malfunctions of electrical equipment can lead to battery discharge

You can check for yourself:

  • fuses
  • alternator belt tension
  • voltage regulator
  • wiring status
  • battery
  • alternator
  • leakage current

Defective parts should be replaced with new ones.

How can I avoid operating errors that may discharge the battery?

When connecting heaters, audio/video devices, light sources, and other power consumers to the car’s onboard network, make sure that the generator has sufficient power reserve to power additional devices.

When standing in traffic jams for a long time, keep in mind that the generator gives full power only when the engine speed exceeds 1500, and at idle speed, the battery carries part of the load, so in such cases, it is desirable to cut the unnecessary power consumers from the onboard network.

When using cars in the mode of frequent trips for short distances the battery does not have time to be charged from the generator and requires periodic recharging from an external charger.

The most trivial causes of discharge are unplugged parking lights, constantly on trunk lights, and improperly wired alarms.

Do not use fuses with a higher rating than specified in the vehicle owner’s manual.

Protect terminals from oxidation with special products.

Keep them clean to avoid self-discharge through a conductive layer of surface dirt.

When installing a new battery, be sure to completely remove the protective polyethylene film – dust and dirt accumulate underneath.

If you do not intend to use the car for a long time, do not leave the battery connected to the onboard power supply to avoid complete discharge – this can cause a significant loss of capacity due to accelerated sulphation of the plates.

At least once a year, preferably before the onset of cold weather, recharge the battery with a line charger in desulphation mode, check the alternator belt tension, and check the onboard network for leaks.

Be aware of winter use and storage of the vehicle battery!

Proper use and storage during the cold season, as well as preventative measures, will minimize the risk of nasty situations, as usual, at the most inopportune time.

Hi, I'm Paul! And me and my friends created this site to tell you a lot of useful things from the world of batteries. I worked as a salesman in a large auto parts store and have gained a lot of experience in this field, so I am happy to share my knowledge and experience with you.

Rate author
AGM Battery Guide