1. Introduction
The PAC Audio RadioPRO RP4.2-MB11 is a radio replacement interface designed for Mercedes Sprinter and Metris vehicles. This interface facilitates the installation of an aftermarket radio while retaining key factory features. It ensures continued functionality of steering wheel controls, the 3.5mm AUX input, the USB port, and the back-up camera system. The RP4.2-MB11 also supports integration with the PAC VS41 for expanded camera system capabilities, including front and blind-spot cameras.
2. Product Overview and Features
The RP4.2-MB11 interface provides seamless integration of an aftermarket radio with your vehicle's existing systems. Key features include:
- Steering Wheel Control Retention: Maintains the functionality of factory steering wheel audio controls with your new aftermarket radio.
- 3.5mm AUX Input Retention: Preserves the use of the factory 3.5mm auxiliary audio input.
- USB Port Retention: Ensures the factory USB port remains functional.
- Back-Up Camera Function Retention: Continues to display the factory back-up camera feed on the aftermarket radio.
- Rear Camera Activation While in Motion: Allows for activation of the rear camera display even when the vehicle is not in reverse.
- 10 Amp ACC 12 Volt Output: Provides a reliable accessory power output for the aftermarket radio.
- Wired Outputs for Navigation Radio Installation: Includes specific outputs to support navigation features in compatible aftermarket radios.
- Direct USB Updatable: Firmware can be updated via a direct USB connection, ensuring compatibility and access to future enhancements.
3. Package Contents
Verify that all components are present before beginning installation:
- PAC Audio RadioPRO RP4.2-MB11 Interface Module
- Vehicle-specific wiring harness
- 3.5mm AUX input cable
- USB port retention cable
- Back-up camera retention cable
- Steering wheel control interface cable
Image 1: Contents of the PAC Audio RadioPRO RP4.2-MB11 package, showing the main interface module, various wiring harnesses, and adapter cables for AUX, USB, and camera retention.
4. Setup and Installation
Installation of the RP4.2-MB11 requires technical knowledge of car audio systems and vehicle wiring. If you are not comfortable performing this installation, it is recommended to seek professional assistance.
- Vehicle Disassembly: Carefully remove the factory radio and any necessary trim panels to access the vehicle's wiring harness. Refer to your vehicle's service manual for specific instructions.
- Firmware Update (if necessary): Before installation, check the PAC Audio website for the latest firmware for the RP4.2-MB11. If an update is available, follow the instructions provided by PAC Audio to update the module via its USB port. This ensures optimal compatibility and performance.
- Wiring Connections:
- Connect the vehicle-specific wiring harness from the RP4.2-MB11 to the factory radio harness in the vehicle.
- Connect the aftermarket radio's wiring harness to the corresponding wires on the RP4.2-MB11 harness. Ensure all connections (power, ground, speaker, accessory, illumination, etc.) are secure and correctly matched according to the wiring diagrams provided with both the RP4.2-MB11 and your aftermarket radio.
- Connect the 3.5mm AUX input cable, USB port retention cable, and back-up camera retention cable from the RP4.2-MB11 to the appropriate inputs on your aftermarket radio.
- Connect the steering wheel control interface cable from the RP4.2-MB11 to the steering wheel control input on your aftermarket radio (typically a 3.5mm jack or specific wire).
- If installing a navigation radio, connect the dedicated navigation outputs from the RP4.2-MB11 to the corresponding inputs on the navigation unit.
- Module Placement: Securely mount the RP4.2-MB11 module in a location that is free from moisture and excessive heat, and where it will not interfere with vehicle operation.
- Testing: Before reassembling the dashboard, temporarily connect the vehicle battery and test all functions of the aftermarket radio, including audio, steering wheel controls, AUX input, USB port, and back-up camera display.
- Reassembly: Once all functions are verified, carefully reassemble the vehicle's dashboard and trim panels.
5. Operating Instructions
Once installed, the RP4.2-MB11 operates automatically to integrate your aftermarket radio with the vehicle's systems. No specific user interaction with the interface module itself is required.
- Steering Wheel Controls: Use your vehicle's factory steering wheel buttons to control volume, track changes, source selection, and other functions as programmed with your aftermarket radio. Refer to your aftermarket radio's manual for steering wheel control programming details.
- AUX Input: Connect audio devices to the factory 3.5mm AUX input. Select the AUX source on your aftermarket radio to play audio.
- USB Port: Connect USB devices (e.g., flash drives, smartphones for charging/data) to the factory USB port. Select the USB source on your aftermarket radio to access media or charging functions.
- Back-Up Camera: The factory back-up camera image will automatically display on your aftermarket radio screen when the vehicle is shifted into reverse. The RP4.2-MB11 also allows for manual activation of the rear camera while in motion, if supported by your aftermarket radio and configured during installation.
6. Maintenance
The PAC Audio RP4.2-MB11 interface module is designed for maintenance-free operation. No routine maintenance is required.
- Firmware Updates: Periodically check the PAC Audio website for firmware updates. Updates can improve performance, add features, or enhance compatibility with new aftermarket radios or vehicle models.
- Cleaning: Keep the module free from dust and debris. If cleaning is necessary, use a dry, soft cloth. Do not use liquid cleaners or solvents.
7. Troubleshooting
If you encounter issues with your RP4.2-MB11 interface, consider the following troubleshooting steps:
- No Power to Aftermarket Radio:
- Check all power and ground connections to the RP4.2-MB11 module and the aftermarket radio.
- Verify the vehicle's fuse for the radio circuit is intact.
- Steering Wheel Controls Not Functioning:
- Ensure the steering wheel control cable is securely connected to both the RP4.2-MB11 and the aftermarket radio's SWC input.
- Check the aftermarket radio's settings for steering wheel control programming. Some radios require manual programming or auto-detection.
- Confirm the RP4.2-MB11 has the correct firmware for your vehicle and aftermarket radio.
- AUX/USB Port Not Working:
- Verify the respective cables are properly connected from the RP4.2-MB11 to the aftermarket radio.
- Ensure the correct source is selected on the aftermarket radio.
- Test with a different device or cable to rule out external component issues.
- Back-Up Camera Not Displaying:
- Check the camera retention cable connection to the aftermarket radio's camera input.
- Verify the aftermarket radio's settings for camera input and reverse trigger.
- Ensure the vehicle is in reverse when testing (unless manual activation is configured).
- General Malfunction:
- Perform a soft reset by disconnecting the vehicle's battery for a few minutes, then reconnecting it.
- Ensure the RP4.2-MB11 module is securely connected to all harnesses.
- Contact PAC Audio technical support if issues persist after performing these steps.
8. Specifications
| Model Number | RP4.2-MB11 |
| Brand | PAC Audio |
| Product Dimensions | 9 x 9 x 2 inches |
| Item Weight | 11.2 ounces |
| Connectivity Technology | USB |
| Power Source | Corded Electric |
| Retained Features | Steering Wheel Controls, 3.5mm AUX Input, USB Port, Back-Up Camera Function |
| Compatible Vehicles | Mercedes Sprinter, Mercedes Metris |
9. Warranty and Support
For specific warranty information, please refer to the documentation included with your product or visit the official PAC Audio website. PAC Audio provides technical support for their products.
- Manufacturer: PAC Audio
- Website: www.pac-audio.com (Please check for the most current contact and support information)
