3. If the brake fluid level is too low, contact an authorized Volkswagen dealer or authorized Volkswagen Service Facility.
12 V vehicle battery
Introduction
The 12 V vehicle battery is a component of the electrical system and supplies vehicle safety systems with energy if there is high-voltage system malfunction. During
maintenance procedures, the 12 V vehicle battery is checked and replaced if necessary.
You may only perform procedures on the electrical system yourself if you are familiar with the necessary activities and the general safety precautions, and if the
correct operating equipment and fluids and suitable tools are available. Work performed incorrectly can result in serious injuries ⇒
. Have all work performed by
suitably qualified professionals. Volkswagen recommends contacting an authorized Volkswagen dealer or authorized Volkswagen Service Facility.
Information about warning and indicator lights can be found in the troubleshooting section at the end of the chapter ⇒ Troubleshooting.
Battery switch-off in an accident with triggering of the airbag
In vehicles with a 12 V vehicle battery in their vehicle interior or luggage compartment, the electrical connection to the 12 V vehicle battery is pyrotechnically
disconnected in an accident with airbag deployment. This prevents a short circuit. For more information on the installation location of the vehicle battery, refer to
section → page , Checking the 12 V vehicle battery acid level .
Detailed warnings for the 12 V vehicle battery
Always wear eye protection.
are forbidden. A highly explosive mixture of gases forms when charging the 12 V vehicle battery.
V vehicle battery. Always heed the Owner's Manual.
Battery acid is highly corrosive. Always wear protective gloves and eye protection.
Fire, sparks, open flame, and smoking
Always keep children away from battery acid and the 12
WARNING
Performing work on the 12 V vehicle battery and the electrical system can cause serious injuries, fires, or electric shocks. This could result in serious injuries.
Always read and follow the warning information on the 12 V vehicle battery.
Before performing any work on the 12 V vehicle battery, switch off the ignition and all electrical equipment and disconnect the 12 V battery negative
cable.
Always keep children away from battery electrolyte and the 12 V vehicle battery.
When handling 12 V vehicle batteries, always protect your hands, arms, and face from spraying battery acid.
Always wear eye protection and safety gloves.
Never short circuit the battery terminals.
WARNING
When work is carried out on the 12 V vehicle battery, a highly explosive, flammable gas mixture builds up. Sparks could form and ignite the flammable gas that
is released by the 12 V vehicle battery. This can result in serious injury or death.
Always keep fires, sparks, open flames, and lit cigarettes far away from the 12 V vehicle battery.
Avoid creating sparks when working with wires and electrical equipment or when discharging static electricity.
WARNING
A drained 12 V vehicle battery can freeze at temperatures around 0 °C (+32 °F). Acid may leak out of 12 V vehicle batteries that have frozen and thawed again
and cause damage to the vehicle in the long run.
Never charge a frozen or thawed 12 V vehicle battery.
Always replace the 12 V vehicle battery if it freezes.
WARNING
California Proposition 65 Warning.
This product can expose you to chemicals including lead and lead components, which are known to the State of California to cause cancer and birth
NOTICE
UV rays can damage the battery housing.
Do not expose the 12 V vehicle battery to direct sunlight for a long period of time.
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NOTICE
The 12 V vehicle battery could freeze and be destroyed.
Protect the 12 V vehicle battery against freezing temperatures if the vehicle is parked for long periods of time.
After establishing the drive-ready mode when the 12 V vehicle battery is severely drained or replaced or after jump-starting it, the system settings (time, date,
personal convenience settings, and programming) and user profiles may be changed or deleted. Check and correct the settings after the 12 V vehicle battery is
sufficiently recharged.
Checking the 12 V vehicle battery acid level
Please read the introductory information and heed the Warnings and Notice ⇒
and
Safety precautions for working in the hood space .
Check the acid level of the 12 V vehicle battery regularly if mileage is high, in countries with warm climates, or if the 12 V vehicle battery is old. Otherwise, the 12 V
vehicle battery is maintenance-free.
12 V vehicle battery location
The 12 V vehicle battery is located in the hood space.
Checking the battery acid level
In order to check the battery acid level of a 12 V vehicle battery, you must remove the main fuse box on the 12 V vehicle battery. An additional tool that is not
available in the vehicle tool kit is required to do this.
Always have the acid level of the 12 V vehicle battery checked by an authorized Volkswagen dealer or authorized Volkswagen Service Facility. Volkswagen
recommends contacting an authorized Volkswagen dealer or authorized Volkswagen Service Facility.
Charging, replacing, disconnecting, or connecting the 12 V vehicle battery
Please read the introductory information and heed the Warnings and Notice ⇒
and
Safety precautions for working in the hood space .
If you suspect that the 12 V vehicle battery is damaged or malfunctioning, see suitably qualified professionals to have the 12 V vehicle battery checked. Volkswagen
recommends contacting an authorized Volkswagen dealer or authorized Volkswagen Service Facility.
Charging the 12 V vehicle battery
The 12 V vehicle battery should be charged by suitably qualified professionals because the 12 V vehicle battery that is installed at the factory requires a charging
process where the voltage is limited ⇒
. Volkswagen recommends contacting an authorized Volkswagen dealer or authorized Volkswagen Service Facility.
Replacing the 12 V vehicle battery
The 12 V vehicle battery is designed to fit the location where it is installed and is equipped with safety features. If a 12 V vehicle battery needs to be replaced, have
the replacement part fitted by qualified professionals. Volkswagen recommends contacting an authorized Volkswagen dealer or authorized Volkswagen Service
Facility. Check with qualified professionals to find out the component information regarding size and the required maintenance, performance, and safety features.
They must possess the necessary technical documentation and equipment. Volkswagen recommends contacting an authorized Volkswagen dealer or authorized
Volkswagen Service Facility. The vent opening on the 12 V vehicle battery must always be located on the negative terminal side. The vent opening on the positive
terminal side must always be sealed ⇒
.
Only use a maintenance-free 12 V vehicle battery that conforms to the TL 825 06 and VW 7 50 73 standards. These standards must be from October 2014 or later.
Always have the 12 V vehicle battery replaced by qualified professionals because the vehicle electronics must be adapted as part of the replacement. In addition,
the battery parameters for functional safety can only be determined with the OEM battery. Only qualified professionals have the necessary equipment to perform the
adaptation and have access to the correct replacement batteries. Using unsuitable batteries invalidates the operating license.
Disconnecting the 12 V vehicle battery
If the 12 V vehicle battery must be disconnected from the vehicle electrical system, note the following:
1. Switch off all electrical consumers.
2. Disconnect the negative cable first, and then the positive cable ⇒
.
Connecting the 12 V vehicle battery
If the 12 V vehicle battery must be connected to the vehicle electrical system, note the following:
1. Switch off all electrical consumers.
2. Connect the positive cable first, and then the negative cable ⇒
.
Various indicator lights may turn on after connecting the 12 V vehicle battery and switching the ignition on. They will turn off after driving a short distance at a speed
of approximately 15 km/h to 20 km/h (approximately 10 mph to 12 mph). If the indicator lights light up and remain on, contact an authorized Volkswagen dealer or
authorized Volkswagen Service Facility and have the vehicle checked. Volkswagen recommends contacting an authorized Volkswagen dealer or authorized
Volkswagen Service Facility.
If the 12 V vehicle battery was disconnected for a long period of time, the next scheduled maintenance may not display correctly or it may not be calculated correctl
⇒ Service display. Follow the maximum permissible maintenance interval ⇒ Maintenance.
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If the ignition cannot be switched on after connecting the 12 V vehicle battery, carry out the following activities:
1. Lock and unlock the vehicle from the outside.
2. Try to switch the ignition on again.
3. If the ignition will not switch on, see an authorized Volkswagen dealer or authorized Volkswagen Service Facility for assistance.
Automatic equipment deactivation
If the parking light is switched on when parking for a very long time when the vehicle is not drive-ready, the intelligent power management cannot always prevent th
12 V vehicle battery from being drained.
If the 12 V vehicle battery is under a heavy load, the intelligent power management will automatically begin certain measures to prevent the 12 V vehicle battery
from draining.
If necessary, equipment that uses a lot of power will have its performance limited or will be switched off.
12 V Vehicle Battery Draining
If the battery is drained, it may not be possible to activate the vehicle's drive system. The 12 V vehicle battery will be drained in the following situations:
If the vehicle is parked for long periods of time without ensuring that the vehicle is drive-ready.
If electrical equipment is used when the vehicle is not in drive-ready mode.
WARNING
Use of a 12 V vehicle battery that does not have identical specifications and dimensions to the 12 V vehicle battery that was installed at the factory may cause
short circuits or fire. This could result in serious or fatal injuries.
Always use a maintenance-free and leak-proof 12 V vehicle battery that has the same specifications and dimensions as the 12 V vehicle battery that was
installed at the factory.
WARNING
Fitting 12 V vehicle batteries incorrectly may cause short circuits or fire. This could result in serious or fatal injuries.
Always attach the 12 V vehicle battery to the attachment points provided in the vehicle.
Replace all covers that are required for the vehicle back on the battery.
WARNING
A highly explosive mixture of hydrogen gas can form when charging the 12 V vehicle battery. Sparks or naked flames could ignite the gas mixture. Serious
burns may result.
Only charge 12 V vehicle batteries in well-ventilated areas.
Keep sparks and naked flames away from the 12 V vehicle battery.
WARNING
A drained 12 V vehicle battery can freeze at temperatures around 0 °C (+32 °F). Acid may leak out of 12 V vehicle batteries that have frozen and thawed again
and cause damage to the vehicle in the long run.
Never charge a frozen or thawed 12 V vehicle battery.
Always replace the 12 V vehicle battery if it freezes.
WARNING
If the degassing tube is not attached to the 12 V vehicle battery correctly, the highly explosive gas mixture that builds up when the vehicle is running may enter
the vehicle interior. This oxyhydrogen gas can ignite and cause serious or fatal injuries.
For vehicles with the 12 V vehicle battery in the vehicle interior or luggage compartment, ensure that the degassing hose is connected to the 12 V vehicle
battery correctly. The degassing hose must always be connected to the negative terminal side of the 12-volt vehicle battery.
Always ensure that the opening on the positive terminal side of the 12 V vehicle battery is capped.
CAUTION
Cables that are connected incorrectly can cause a short circuit. This could damage the on-board electronics and result in serious injuries.
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Connect the positive cable first and then the negative cable.
NOTICE
If the 12 V vehicle battery is connected or disconnected when the ignition is switched on or the vehicle is drive-ready, this could damage the electrical system or
electronic components, resulting in electrical malfunctions.
Never connect or disconnect the 12 V vehicle battery when the ignition or the vehicle's drive system is switched on.
NOTICE
If accessories that provide power for charging the 12 V vehicle battery are connected to the 12 V socket, this could damage the electrical system or electronic
components, resulting in electrical malfunctions.
Never connect accessories that provide power, such as solar panels or battery chargers, to the 12 V socket in order to charge the 12 V vehicle battery.
12 V vehicle batteries can contain toxic substances such as sulfuric acid and lead. Dispose of 12 V vehicle batteries correctly.
Battery acid can pollute the environment. Collect spilled battery acid and dispose of it correctly.
Troubleshooting
Please read the introductory information and heed the Warnings and Notice ⇒
and
Safety precautions for working in the hood space .
12-volt power supply
The red warning light turns on. A message is shown in the instrument cluster display.
Do not continue driving! Possible failure of the electrical system.
1. Stop the vehicle immediately and park it safely.
2. Turn off electrical equipment that is not needed.
3. End drive-ready mode.
4. Contact an authorized Volkswagen dealer or authorized Volkswagen Service Facility for assistance.
12-volt power supply
The yellow indicator light turns on. A message is shown in the instrument cluster display.
Messages about the battery charge level of the 12 V vehicle battery.
1. Switch on the ignition so that the 12 V vehicle battery can be recharged.
Or: Charge the 12 V vehicle battery by charging the high-voltage battery.
2. If the message about the battery charge level of the 12 V vehicle battery does not turn off after a few minutes despite the measures having been taken, then
contact an authorized Volkswagen dealer or authorized Volkswagen Service Facility.
Messages about the 12 V power supply.
1. Contact an authorized Volkswagen dealer or authorized Volkswagen Service Facility for assistance.
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2024 VW ID.4 Owner's Manual
