Replacing a brake light switch is a relatively simple task that can be completed in about 30 minutes. If your brake lights are not working, it is possible that the switch has failed. The brake light switch is located under the dashboard, near the brake pedal. To replace the switch, you will need a new switch, a socket wrench, and a Phillips screwdriver. You should also disconnect the negative terminal of the battery before starting work.
Once you have disconnected the battery, you can begin by removing the two screws that hold the switch in place. Then, pull the switch straight out of its socket. Be careful not to damage the wiring when you are removing the switch. Next, take the new switch and insert it into the socket. Tighten the two screws that hold the switch in place. Finally, reconnect the negative terminal of the battery and test the brake lights to make sure that they are working properly.
Removing the Lower Dash Panel
1. Open the driver’s door and locate the lower dash panel beneath the steering wheel.
2. Grip the panel firmly and pull it straight towards you to detach it from the dashboard. If the panel resists, gently pry it loose using a plastic trim tool to avoid damaging the clips.
3. Once the panel is detached, set it aside in a safe place for later reassembly.
4. Locate the brake light switch behind the lower dash panel, typically situated near the brake pedal.
5. Disconnect the electrical connector from the brake light switch by pressing on the release tab and gently pulling the connector away.
6. Use a 10mm socket or wrench to loosen and remove the mounting bolt securing the brake light switch to the mounting bracket.
7. Carefully remove the old brake light switch from the mounting bracket and replace it with the new one.
8. Tighten the mounting bolt to secure the new brake light switch to the bracket.
9. Reconnect the electrical connector to the new brake light switch.
10. Reattach the lower dash panel to the dashboard by aligning it properly and pressing it firmly into place until it snaps securely.
| Tools Needed: | Estimated Time: |
|---|---|
| Plastic trim tool | 30 minutes |
| 10mm socket or wrench |
Unplugging the Brake Light Switch Connector
The brake light switch connector is located on the upper side of the brake pedal arm. It has a plastic locking tab that must be released before the connector can be unplugged. To do this:
- Locate the brake light switch connector on the upper side of the brake pedal arm.
- Use a small flat-head screwdriver or a trim removal tool to gently pry up the plastic locking tab on the connector.
- Once the locking tab is released, carefully pull the connector straight up to unplug it from the brake light switch.
**Note:** Be careful not to damage the brake light switch connector or the wiring when unplugging it.
Additional Information
The brake light switch is an important electrical component that activates the brake lights when the brake pedal is depressed. It is a relatively simple device, but it can fail over time, leading to brake light failure. If you suspect that your brake light switch may be faulty, it is important to inspect and replace it as soon as possible to ensure that your brake lights are functioning properly.
| Symptom | Possible Cause |
|---|---|
| Brake lights do not come on when the brake pedal is depressed | Faulty brake light switch |
| Brake lights stay on even when the brake pedal is not depressed | Faulty brake light switch |
| Brake lights flicker or dim when the brake pedal is depressed | Loose or damaged brake light switch connector |
Removing the Brake Light Switch
To remove the brake light switch, follow these steps:
1. Gather Tools
You will need the following tools:
- Phillips head screwdriver
- Flathead screwdriver
- Socket wrench with 10mm socket
- Pliers
- Electrical tape
2. Disconnect Negative Battery Terminal
Locate the negative battery terminal and use a 10mm socket wrench to disconnect it. This will prevent any electrical shock or damage to the vehicle’s electrical system.
3. Locate the Brake Light Switch
The brake light switch is usually located on the firewall, near the brake pedal. It is a small, black switch with two wires connected to it.
4. Remove Electrical Connector and Unbolt Switch
Use your flathead screwdriver to gently pry the electrical connector off of the brake light switch. Do not pull on the wires, as this could damage them.
Now, use your Phillips head screwdriver to unbolt the brake light switch from the firewall. Be careful not to drop the bolts or lose them.
| Step | Description |
|---|---|
| 4a | Using your pliers, slightly squeeze the plastic tabs on the electrical connector and pull it straight off the brake light switch. |
| 4b | Locate the two bolts that hold the brake light switch in place using your Phillips head screwdriver. |
| 4c | Carefully unscrew the bolts counterclockwise and remove the brake light switch from the firewall. |
Installing the New Brake Light Switch
1. Safety First: Before you start, ensure your Audi is parked safely in the park position, and the engine is turned off. Disconnect the battery’s negative terminal to prevent any electrical accidents.
2. Accessing the Brake Light Switch: Locate the brake light switch, typically situated above the brake pedal arm. In most 2007 Audi A4 models, you can access it by removing the lower dash panel beneath the steering column.
3. Unplug the Old Switch: Once you’ve found the brake light switch, press the release tab and disconnect the electrical connector.
4. Removing the Old Switch: Using a socket wrench or spanner, loosen and remove the mounting nut holding the brake light switch in place. Carefully pull the old switch out of its socket.
5. Installing the New Switch:
- Align the new brake light switch with the socket and push it firmly into place.
- Tighten the mounting nut securely to hold the switch in position.
- Reconnect the electrical connector by pressing down on the release tab and inserting it into the switch.
Reinstalling the Lower Dash Panel
Now that the new brake light switch is installed, it’s time to put everything back together. Begin by aligning the lower dash panel with the dashboard and carefully sliding it into place.
Next, secure the panel with the four screws that you removed earlier. Make sure to tighten the screws securely, but don’t overtighten them.
Once the lower dash panel is in place, reattach the center console trim by sliding it up into position and securing it with the two screws.
Finally, reconnect the negative battery terminal.
Important Note
After reinstalling the battery, you may need to reset certain settings in your Audi, such as the clock and radio presets. Consult your vehicle’s owner’s manual for specific instructions on how to perform these resets.
Testing the Brake Lights
Before replacing the brake light switch, it’s important to verify that the brake lights are not working. Follow these steps to test the brake lights:
1. Park the car on a flat surface and engage the parking brake.
2. Turn on the ignition but do not start the engine.
3. Press the brake pedal and observe if the brake lights are illuminated.
4. If the brake lights are not illuminated, repeat step 3 while someone observes the brake lights from outside the car.
5. If the brake lights still do not illuminate, there may be an issue with the brake light switch or another part of the brake light circuit.
6. Check the brake light bulbs to ensure they are not burnt out.
7. Inspect the brake light wiring for any damage or loose connections.
8. If you have access to a scan tool, connect it to the car’s diagnostic port and check for any fault codes related to the brake light switch or brake light circuit. Common fault codes associated with brake light issues include:
| Fault Code | Description |
|---|---|
| B10DD | Brake light switch circuit open |
| B10DE | Brake light switch circuit short to ground |
| B10DF | Brake light switch circuit short to voltage |
9. If you have ruled out all other potential causes, it is likely that the brake light switch needs to be replaced.
Troubleshooting Common Issues
1. Brake Light Switch Remains Active
This issue can be caused by a faulty brake light switch or a wiring problem. Inspect the switch for damage or loose connections, and check the wiring for any breaks or shorts.
2. Brake Lights Do Not Activate When Pedal Pressed
The problem could lie with the brake light switch, the brake pedal, or the wiring. Ensure the switch is securely connected and not damaged, then inspect the brake pedal for any obstructions or misalignment.
3. Brake Lights Stay On After Pedal Release
This issue may indicate a faulty brake light switch or a wiring problem. Replace the switch and check the wiring for any shorts or grounds.
4. Brake Lights Too Bright/Dim
This issue can be caused by a faulty brake light switch or a problem with the electrical system. Inspect the switch for damage or loose connections, and check the battery and alternator for any issues.
5. Brake Lights Flickering
Flickering brake lights can be caused by a loose connection or a faulty brake light switch. Ensure all connections are secure and replace the switch if necessary.
6. Dashboard Warning Light Stays On
If the brake light warning light on the dashboard remains illuminated after starting the vehicle, it could indicate a faulty brake light switch or a wiring issue. Inspect both the switch and the wiring.
7. Fuse Blowing
A blown fuse can be caused by a short circuit in the wiring or a faulty brake light switch. Replace the fuse and inspect the wiring and switch for any damage or issues.
8. Brake Pedal Feels Spongy
A spongy brake pedal can be caused by a problem with the master cylinder, brake lines, or brake pads. Inspect these components and replace any faulty parts as needed.
9. Diagnosis Using OBD-II Scanner
An OBD-II scanner can provide detailed information about the brake light switch and other system components. Connect the scanner to the vehicle’s OBD-II port and scan for any fault codes related to the brake light switch. Refer to the vehicle’s service manual for the specific diagnostic codes and troubleshooting steps.
| Fault Code | Description |
|---|---|
| C1100 | Brake Light Switch Circuit Malfunction |
| C1101 | Brake Light Switch Signal Circuit Open |
| C1102 | Brake Light Switch Signal Circuit Short to Ground |
Safety Tips
Before beginning any electrical work, disconnect the negative battery terminal. This will prevent any electrical shocks or damage to the vehicle’s electrical system.
Wear safety glasses and gloves when working with electrical components.
Do not attempt to repair or replace electrical components if you are not qualified to do so. Consult a qualified mechanic if you have any doubts.
Place the new brake light switch in the correct position.
Tighten the brake light switch mounting bolts to the specified torque.
Connect the electrical connector to the brake light switch.
Reconnect the negative battery terminal.
Test the brake lights to ensure that they are working properly.
Special Note:
If the brake lights do not work after replacing the brake light switch, the problem may be with the brake light bulbs or the wiring. Consult a qualified mechanic to diagnose and repair the problem.
2007 Audi A4 Brake Light Switch Installation
Replacing the brake light switch on a 2007 Audi A4 is a relatively simple task that can be completed in about 30 minutes. The brake light switch is located on the top of the brake pedal assembly, and it activates the brake lights when the pedal is depressed. If your brake lights are not working, the brake light switch may be faulty and need to be replaced.
To replace the brake light switch, you will need the following tools:
- 10mm socket wrench
- Phillips head screwdriver
- New brake light switch
Once you have gathered your tools, follow these steps to replace the brake light switch:
1. Park the car in a safe location and turn off the engine.
2. Disconnect the negative terminal of the battery.
3. Remove the plastic cover from the steering column.
4. Locate the brake light switch on the top of the brake pedal assembly.
5. Disconnect the electrical connector from the brake light switch.
6. Remove the two 10mm bolts that hold the brake light switch in place.
7. Pull the brake light switch out of the brake pedal assembly.
8. Install the new brake light switch into the brake pedal assembly.
9. Tighten the two 10mm bolts that hold the brake light switch in place.
10. Connect the electrical connector to the brake light switch.
11. Replace the plastic cover on the steering column.
12. Connect the negative terminal of the battery.
13. Test the brake lights to make sure they are working properly.
People Also Ask
How do I know if my brake light switch is bad?
There are a few signs that your brake light switch may be bad, including:
- The brake lights do not come on when the brake pedal is depressed.
- The cruise control does not work.
- The transmission will not shift out of park.
Can I drive with a bad brake light switch?
It is not safe to drive with a bad brake light switch. If the brake lights are not working, other drivers will not be able to see when you are braking, which could lead to an accident.
How much does it cost to replace a brake light switch?
The cost to replace a brake light switch will vary depending on the make and model of your car. However, the average cost is between $50 and $100.
