Where to Find the Battery in a 2007 Audi A4

The main battery in a 2007 Audi A4 is located in the trunk, on the right-hand side beneath a removable cover in the luggage compartment, not under the hood. While the engine bay contains power distribution points for jump-starting, the actual 12-volt battery that powers the vehicle is mounted in the rear for weight balance and packaging reasons.

Understanding the Battery Location in the 2007 Audi A4

The 2007 Audi A4, including most B7-generation models (sedan, Avant/wagon, and some S4 variants), uses a trunk-mounted battery layout. This design can be confusing to owners who expect to find the battery under the hood. Instead, Audi routes heavy-gauge cables from the rear-mounted battery to connection points in the engine bay, which are provided for convenience when jump-starting or testing charging voltage.

Primary Battery Location: In the Trunk

For most owners, the key detail is that the battery is in the rear of the car. Accessing it requires opening the trunk and lifting or removing interior trim panels on the passenger side (right side on left-hand-drive cars). This configuration is standard on the majority of 2007 A4 models, including many versions sold in North America and Europe.

Step-by-Step: How to Access the Battery in the Trunk

The following steps outline how to safely access the battery in the trunk of a 2007 Audi A4 so you can inspect, test, replace, or disconnect it when needed.

1. Open the trunk and ensure the vehicle is parked securely on a level surface with the ignition off and key removed.
2. Look to the right-hand side of the trunk (passenger side in left-hand-drive cars) for a carpeted side panel or access door in the trunk lining.
3. Release or pull back the side panel: some models have a small plastic handle or tab; others require gently pulling the carpeting away from the side wall.
4. Behind this panel, you will see the battery mounted in a recessed compartment, secured by a bracket or clamp at the base.
5. Inspect the battery terminals and surrounding area for corrosion, loose connections, or moisture before proceeding with any work.
6. When disconnecting, always remove the negative (–) terminal first, then the positive (+) terminal to reduce the risk of short circuits.
7. If removing the battery, undo the retaining clamp or bracket, then carefully lift the battery straight up; it is heavy, so use proper lifting posture.

Once you are familiar with the access panel and the retaining hardware, reaching the trunk-mounted battery becomes a straightforward routine task, whether you are replacing it or performing maintenance.

What You’ll Find Under the Hood

Many Audi A4 owners initially look under the hood for the battery and are surprised when they cannot find it. Instead of the full battery, the engine bay contains designated terminals and power distribution points designed for jump-starting and diagnostic work.

Jump-Start Terminals Under the Hood

Even though the battery is in the trunk, Audi provides accessible connection points in the engine bay. These are crucial if you need to jump-start the car or connect a charger without pulling back trunk trim.

• A covered positive (+) terminal is typically located on or near the firewall or in the main fuse/relay area under a plastic cover.
• A solid engine or chassis ground point serves as the negative (–) connection for jump cables or a battery charger.
• The cables from these points run back to the battery in the trunk, allowing safe current flow without direct access to the battery itself.
• Using these points is generally safer and quicker than accessing the battery in the trunk for jump-starting, especially in bad weather or tight parking spaces.
• Always follow the order: connect positive to positive, then negative to a solid ground on the disabled car, and disconnect in reverse order.

These remote terminals ensure that standard battery-related operations, such as jump-starting or basic voltage checks, can be done from the engine bay without needing to uncover the trunk compartment every time.

Why Audi Puts the Battery in the Trunk

The trunk-mounted battery in the 2007 Audi A4 is not an arbitrary design choice. It reflects a broader trend in premium European vehicles, where battery positioning is used to improve driving dynamics, safety, and packaging efficiency.

Design and Engineering Reasons

The placement of the battery in the trunk offers several benefits that align with Audi’s overall engineering approach for the A4 platform.

• Improved weight distribution: Moving the heavy battery to the rear helps balance front-heavy weight from the engine and transmission, contributing to more stable handling.
• Engine bay packaging: Relocating the battery frees space under the hood for components like air boxes, turbo plumbing (on certain variants), and crash-structure elements.
• Crash safety considerations: Keeping the battery out of the front crumple zone can reduce the risk of battery damage and short circuits in frontal impacts.
• Thermal management: The trunk area is less exposed to extreme engine-bay heat cycles, which can help extend battery life compared with some under-hood locations.
• Noise and vibration tuning: Removing heavy components from the engine compartment can help engineers fine-tune noise, vibration, and harshness characteristics.

Taken together, these design reasons explain why Audi chose a rear-mounted battery for the 2007 A4, even though it can surprise owners used to traditional under-hood layouts.

Model and Market Variations

While the trunk position applies broadly, it is worth recognizing that certain details can vary slightly between trims, body styles, and markets. Nonetheless, the fundamental answer remains the same: in the 2007 A4, you should expect the main 12-volt battery to be in the luggage compartment.

Sedan vs. Avant and S-Line/S4 Considerations

Most differences you will see among 2007 A4 variants relate more to trim pieces than to the battery’s core location.

• Both sedan and Avant (wagon) models typically position the battery on the right-hand side of the trunk behind a trim panel.
• S-Line and some performance-oriented trims may have slightly different carpeted panels, but the access method and battery position are essentially the same.
• Certain high-performance variants (such as some S4 models on the same platform) also use rear-mounted batteries with comparable access points.
• Right-hand-drive markets may mirror some trim details, but the battery is still in the rear luggage compartment area.
• Audio, navigation, or amplifier modules may share space in the trunk, so you may see additional wiring or components near the battery compartment.

These minor differences in trim and layout do not change the underlying fact that owners of 2007 A4 models should look to the rear trunk area, not the engine bay, when seeking the actual battery.

Practical Tips for Working With the Battery

Once you know where the battery is, a few practical measures can help ensure safety and protect your vehicle’s electronics when disconnecting or replacing it.

Safety and Maintenance Advice

The following points outline best practices for handling the battery in a 2007 Audi A4, whether you are doing basic maintenance or a full replacement.

• Always switch off the ignition, remove the key, and keep the car stationary with the parking brake applied before accessing the battery.
• Wear eye protection and gloves when working around the battery to protect against acid, sparks, or accidental short circuits.
• Disconnect the negative (–) terminal first and reconnect it last to reduce the risk of accidental grounding with tools.
• Use a memory saver or be prepared for electronic systems (radio presets, clock, and some comfort settings) to reset after battery disconnection.
• Choose a replacement battery that matches the original specifications (capacity, cold-cranking amps, and physical size) recommended for the 2007 A4.
• Secure the new battery firmly with the hold-down bracket to prevent movement, which can damage wiring or connections over time.
• After installation, check that all connections are tight and that no cables are pinched by the trim when you refit the trunk panel.

Following these steps helps protect both you and the vehicle, ensuring reliable starting performance and preserving the longevity of the electrical system after any battery-related work.

Summary

In a 2007 Audi A4, the main 12-volt battery is located in the trunk, on the right-hand side behind a removable interior panel in the luggage compartment, not under the hood. The engine bay offers dedicated jump-start terminals, but the actual battery sits in the rear to improve weight distribution, packaging, and safety. Owners accessing or replacing the battery should open the trunk, remove the right-side trim panel, and follow standard safety procedures when disconnecting and reconnecting the terminals.

Where is the battery on an Audi A4?

The battery on most modern Audi A4 models (B8 and newer) is located in the trunk (boot), underneath the spare tire. For older models (B6 and some B7), it is located under the hood, near the firewall. You can jump-start a modern A4 from terminals under the hood, even though the main battery is in the trunk.
 
This video shows the location of the battery in the trunk of an Audi A4: 58sTotal TechnikYouTube · Jun 19, 2021
On modern Audi A4s (e.g., 2008-2016 B8 model and later) 

• Location: In the trunk (boot), beneath the spare tire. 
• Access: Lift the trunk floor mat and remove the spare wheel and any tools or covers to get to the battery. 
• Jump-starting: You do not need to access the battery in the trunk to jump-start the car. Use the dedicated jump-start terminals located in the engine bay. The positive terminal is under a red cover in the center, and the negative terminal connects to an unpainted metal surface on the bodywork. 

On older Audi A4s (e.g., 2004-2007 B6/B7 models)

• Location: Under the hood, near the firewall, behind a plastic cover. 
• Access: Remove the plastic cover in the engine bay to reveal the battery. 

What kind of battery does a 2007 Audi A4 take?

Duralast Group Size 94R H7 Battery H7-DL.

Is the Audi A4 battery in the trunk?

It. It’s in the back in the trunk just like that. So now you.

How to start Audi A4 with dead battery?

There’s a little tab right here you push it back and then you pull up. Yeah yeah that’s where it’s fun all right pull up. So right there is the positive terminal.