Volkswagen ID.4: Checking the Brake Fluid

Preparations

1. Park the Volkswagen ID.4 securely on a flat, stable surface.

2. Open the hood to access the brake fluid reservoir.

Checking the Brake Fluid Level

Fig. 1 In the hood space: Cap on the brake fluid reservoir.

The brake fluid reservoir in the Volkswagen ID.4 can be identified by its clearly marked cap → fig. 1.

On some Volkswagen ID.4 models, surrounding components may partially obstruct the view of the fluid level. If the level cannot be clearly seen, professional inspection by an authorized Volkswagen service provider is recommended.

The brake fluid level must always remain between the MIN and MAX markings on the reservoir → .

A slight drop in brake fluid level during operation is normal in the Volkswagen ID.4, as brake pads wear and automatically adjust.

WARNING

Low brake fluid level or incorrect brake fluid can impair braking performance or lead to complete brake failure.

Accidents and serious or fatal injuries may result.

• Inspect the brake system and fluid level regularly.
• Always use the correct brake fluid for the Volkswagen ID.4.
• Only use brake fluid that meets VW standard 501 14.
• If unavailable, only use high-quality alternatives meeting DIN ISO 4925 CLASS 6 or FMVSS 116 DOT 4 in exceptional cases.

Changing brake fluid

The brake fluid in the Volkswagen ID.4 must be replaced at regular service intervals. Authorized Volkswagen service centers can provide the exact maintenance schedule. Always ensure that only approved brake fluid is used during replacement procedures.

WARNING

Brake fluid absorbs moisture over time. This can lead to vapor lock during heavy braking, reducing braking efficiency and potentially causing total brake failure.

• Replace brake fluid at recommended intervals.
• Always use fresh, approved brake fluid.

Troubleshooting

Brake fluid level

The red warning indicator lights up, signaling that the brake fluid level in the Volkswagen ID.4 is too low.

Do not continue driving! This may result in brake system failure.

1. Stop the Volkswagen ID.4 immediately in a safe location (→ Parking).

2. Check the brake fluid level.

3. If the level is low, contact an authorized Volkswagen dealer or service facility without delay.

Introduction

The 12 V battery in the Volkswagen ID.4 plays a crucial role in powering essential safety systems, especially in the event of a high-voltage system malfunction. During maintenance, this battery must be inspected and replaced if necessary.

Only perform work on the Volkswagen ID.4 electrical system if you are fully familiar with the procedures, safety requirements, and have the proper tools and equipment available.

Incorrect handling can result in serious injuries → . Always rely on qualified professionals when necessary.

Additional information about warning lights can be found in the troubleshooting section (→ 12-V vehicle battery).

Battery switch-off in an accident with triggering of the airbag

In the Volkswagen ID.4, if an accident occurs and airbags deploy, the 12 V battery is automatically disconnected via a pyrotechnic system. This prevents short circuits and enhances safety.

Detailed warnings for the 12 V vehicle battery

Always wear eye protection.

  Battery acid is highly corrosive. Always wear protective gloves and eye protection.

Fire, sparks, and open flames are strictly prohibited.

  Explosive gases may form during charging of the 12 V battery.

Always keep children away from the battery and acid.

Always follow the Owner's Manual instructions.

WARNING

Working on the 12 V battery and electrical system of the Volkswagen ID.4 can cause electric shocks, fires, or serious injuries.

• Always follow all safety instructions.
• Switch off ignition and disconnect the negative terminal before working.
• Keep children away from the battery.
• Protect skin and eyes from battery acid.
• Wear safety gloves and protective eyewear.
• Never short-circuit battery terminals.

WARNING

Explosive gases may form when working with the 12 V battery. Sparks can ignite these gases and cause severe injuries or death.

• Keep all ignition sources away.
• Avoid creating sparks.

WARNING

A discharged 12 V battery may freeze at low temperatures. Acid leakage can cause long-term damage.

• Never charge a frozen battery.
• Replace any frozen battery immediately.

NOTICE

UV exposure can damage the battery housing.

• Avoid prolonged exposure to direct sunlight.

NOTICE

Low temperatures can damage the battery.

• Protect the 12 V battery from freezing conditions.

After reconnecting or replacing the 12 V battery in the Volkswagen ID.4, system settings such as time, date, and user preferences may be reset. Check and restore settings once the battery is fully charged.