Upgrade Your Ride: Installing Aftermarket CarPlay in Your Mercedes C250

Is your Mercedes C250 feeling a little dated when it comes to in-car technology? While these cars are renowned for their luxury and driving experience, the infotainment systems can leave something to be desired by today’s standards. If you’re yearning for seamless smartphone integration, navigation apps, and voice control in your C250, you’re in luck. Installing an Aftermarket Carplay For C250 Mercedes Benz is a fantastic DIY upgrade that can bring your classic Benz into the modern era.

Why Choose Aftermarket CarPlay for Your C250?

The factory infotainment system in many Mercedes C250 models, particularly those from the W204 generation, lacks the smartphone mirroring capabilities we’ve come to expect. Features like Apple CarPlay and Android Auto weren’t standard, leaving drivers reliant on outdated navigation, limited app access, and less intuitive interfaces.

Enter aftermarket CarPlay solutions. These clever devices bridge the gap, injecting modern functionality into your existing system. Imagine effortless access to:

Navigation: Use your favorite apps like Google Maps, Waze, or Apple Maps directly on your car’s screen, with real-time traffic updates and intuitive guidance.
Music and Audio Apps: Stream music from Spotify, Apple Music, or podcasts from your phone, all controlled through the familiar CarPlay interface.
Hands-free Calling and Messaging: Make calls, send texts, and listen to voicemails without taking your hands off the wheel, thanks to Siri or Google Assistant integration.
Siri and Voice Control: Control CarPlay features with voice commands, keeping your focus on the road.

While several vendors offer aftermarket CarPlay solutions for the C250, including Unique Auto Developments and Joyauto, the Road Trip CarPlay kit stands out as a popular and user-friendly DIY option. It often provides a balance of features, ease of installation, and value, making it a compelling choice for upgrading your aftermarket carplay for c250 mercedes benz.

Step-by-Step CarPlay Installation Guide for Mercedes C250 (W204)

This guide will walk you through the installation process, drawing on the experience of a fellow Mercedes enthusiast. Remember to always exercise caution when working with your car’s electronics and consult professional help if you’re unsure at any step.

Preparation and Tools

Before you begin, gather the necessary tools to ensure a smooth and damage-free installation. A quality trim removal kit is essential. These kits, readily available online, provide specialized plastic tools designed to pry and pop off interior trim panels without scratching or breaking them. A recommended kit includes a variety of prying tools and potentially clip pliers, making the job significantly easier.

Accessing the Head Unit

The first stage involves safely accessing the Mercedes C250’s head unit (radio) to connect the CarPlay module.

Remove the Front Trim: Start by removing the trim piece located above the radio, incorporating the air vents and the decorative “swish” that extends towards the door. Using a trim removal tool, gently pry behind the trim, starting near the door. The clips should release fairly easily until you reach the vents. The vent section requires more pressure, but with firm, even pressure, it will pop off.
Disconnect the Vent Wire: Once the front trim is removed, disconnect the wiring harness connected to the vent assembly and set the trim piece aside.
Prepare Glove Box Access: To create space for the CarPlay module, you’ll need to access the area behind the glove box. Begin by entering the passenger side footwell and locating three screws securing the lower trim panel beneath the dashboard. Remove these screws. Once loose, pull the trim panel downwards slightly and reach behind it to find a large “L” shaped hook. You may need to move this hook to the left to release the trim. Then, carefully wiggle the trim panel out and disconnect the passenger footwell light wire.
Remove Side Trim: Use your trim removal tool to pry off the trim piece situated on the far right side of the dashboard, between the glove box and the passenger door. This piece is held in place by four pop-out clips and should wiggle free once the clips are released.
Loosen Glove Box: With the side trim removed, you can now access the first glove box screw, located at the bottom where the side trim was removed. Locate the matching screw on the opposite side of the glove box and remove it as well.
Remove Glove Box Screws: Open the glove box and locate four screws at the top, inside the glove box compartment. Remove these screws.
Detach Glove Box: Your glove box should now be ready to be detached. Pull it down and away with a gentle wiggle. Disconnect all wiring harnesses connected to the glove box and move it out of the way to provide ample working space.
Access Radio Screws: With the glove box removed, you can now access the two locking screws securing the radio unit. These are located at the top of the radio cavity, where the vent assembly was positioned. Identify the two silver screws at the top. These screws engage a mechanism that locks the radio onto rails. Unscrew these two screws.
Release Radio Lock: After unscrewing the locking screws, insert your screwdriver back into the screw holes. Give the screwdriver a firm but gentle bump with your palm. This action will knock the security rails down, releasing the radio locking mechanism and allowing the radio to slide out.
Slide Out the Radio: Carefully slide the radio unit out of the dashboard.
Locate Main Wiring Block: Identify the main wiring block on the back of the radio. This is a large, square plastic connector, typically located towards the driver’s side on the bottom of the radio. There’s a lever on the edge of this block. Pull back on this lever to release the harness.
Fiber Optic Cable Transfer (If Applicable): Examine the removed harness. Check if you have two fiber optic wires (often orange) entering the upper right section of the connector. If present, use a pin tool from your trim kit to depress the lock on each fiber optic cable and gently pull them out. It’s crucial to transfer these fiber optic cables to the same positions on the new pigtail harness that comes with the Road Trip kit.
LVDS Cable Connection: Locate the LVDS cable on the back of the radio. In some C250 models (like the W204), this cable might be GRAY, not blue as some instructions may indicate. Disconnect the GRAY LVDS cable. Connect the disconnected GRAY plug into the BLUE splitter cable provided in the Road Trip kit. Then, connect one end of the splitter (the blue plug) back into the GRAY input on the radio, and the other end of the splitter to the Road Trip CarPlay module.
Connect Wiring Block Pigtail: Connect the wiring block pigtail harness from the Road Trip kit into the radio’s main wiring connector. Push the lever down to secure and lock the pigtail harness into place.

Connecting the CarPlay Module (Road Trip)

Set Jumpers: On the Road Trip CarPlay module itself, locate the jumper settings. Consult the Road Trip manual specific to your Mercedes C250 model year (W204). For a 2014 C300 W204, the recommended jumper settings are typically to have jumpers ON for positions 3, 5, and 8, and OFF for all others. Verify the correct settings for your specific model in the manual.
Route Wires and Place Module: Route the wiring from the radio compartment through the hole that leads to the glove box cavity. This hole is often the same one that the vent wiring passes through. There may be two holes; the one closer to the engine bay is often preferable as it provides better clearance when tucking wires. Position the Road Trip module in the space between the radio compartment and the glove box. This area often provides a snug fit for the module, eliminating the need for additional securing. Orient the module with the connectors facing upwards and the wireless antenna wire pointing downwards for optimal placement.

Audio Connection (AUX)

The Road Trip CarPlay module utilizes your car’s AUX input for audio output. The location of your AUX port will determine the next steps.

If your AUX port is conveniently located in the glove box, you can simply run the provided 3.5mm audio cable to it. However, if your AUX port is in the center console storage (as in the original example), a more involved routing process is needed to conceal the audio cable.

Remove Shifter Boot: Use a pry tool to gently pry up the shifter boot. It’s held in place by four snaps and should detach easily.
Remove Shift Knob: Turn the shifter boot inside out over the shift knob to expose the retainer nut. Twist this nut counter-clockwise and pull it down the shaft. You can then pull the shift knob and boot straight off the shaft. (You may need to shift the car into neutral to remove the knob, remember to put it back in park afterward).
Remove Aluminum Trim: Use a pry tool to remove the aluminum trim piece that the shifter boot snapped into. This piece is held on more firmly, so you may need to use a combination of prying and hand-pulling to pop it off.
Access Center Console Storage: Pull out the rubber liner from the small storage compartment in the center console. This will reveal a Torx screw. Remove this screw.
Remove Center Trim: Once the screw is removed, pry up the trim piece that the screw secured. It has four clips that should release if you gently pry at a corner.
Locate Console Screws: With the trim removed, you’ll find three more Torx screws. One holds the COMAND system in place, and the others secure the remaining console trim.
Route Audio Cable: With the trim loosened, you should be able to see under the center console, potentially even seeing the painted metal of the car’s chassis. Use tools from your trim kit to carefully push the 3.5mm audio cable upwards towards the carpet seam located near the shift knob. This seam is an ideal spot to feed the 3.5mm connector upwards and retrieve it. Feed enough wire so that it starts to gather near the shifter opening. You can then reach in and pull the wire through. Now the majority of the audio cable will be hidden beneath the console trim.
Access Storage Compartment Insert: Open your center console storage compartment. If you have a USB and accessory plug inside, there will likely be a black hard plastic liner clipped into the compartment. Use a pry tool to carefully pop off this liner from the side of the storage compartment. This will loosen the insert, allowing you to move it slightly. (Don’t try to fully remove it as it’s screwed in from the bottom, which requires significant console disassembly).
Fish Audio Cable: Take a coat hanger and create a small loop at one end to prevent snagging. Bend the looped end at about a 45-degree angle. Insert the hanger behind the loosened insert in the storage compartment and carefully wiggle it around until the looped end appears at the opening in the center console, just below where the cup holders are located. Pull the hanger upwards so you can attach the 3.5mm connector to it.
Connect to AUX Adapter: Attach the 3.5mm connector to the hanger and carefully pull the hanger back, guiding the connector behind the storage compartment insert. The 3.5mm plug should now be positioned inside the console box. Connect it to the provided adapter and plug it into the AUX port. Tuck the adapter and any excess wire behind the plastic insert, into the cavity behind it, to create a clean and hidden installation.
Reassemble Center Console: With some pressure (due to the audio cable pushing upwards), pop the storage compartment insert back into place on the sides of the compartment. Gather any slack in the audio cable and tuck it under the center console trim. Reassemble the center console trim pieces, shifter trim, and shift knob in reverse order of removal.

Testing and Reassembly

Initial Testing

Power On and Test: Before fully reassembling everything, it’s crucial to test the CarPlay installation. Turn on your car’s ignition. Connect your phone to the USB port (for initial testing, this will work for both wired and wireless CarPlay/Android Auto). Press and hold the “CLEAR” button on your center console COMAND system. CarPlay should appear on your screen.
Verify Functionality: Check that you can hear audio, navigate through the CarPlay interface using the COMAND dial, and test basic functions like music playback and navigation.
Troubleshooting:
- No Screen Display: Double-check the GRAY LVDS cable connection and the splitter to ensure they are securely plugged in.
- No Sound: Verify the 3.5mm audio cable connection to the AUX port is secure.
- No Power/CarPlay Activation: Check the main wiring block connection at the back of the radio to ensure it’s locked in place.

Reassembly

Reverse Installation: Once you’ve confirmed everything is working correctly, begin the reassembly process by reversing the steps you took for disassembly.
Radio Placement and Locking: Slide the radio back into its cavity until it’s about 2 inches from being fully seated. Tuck the large wiring block pigtail into a void beneath the radio, ensuring it’s neatly positioned. As you slide the radio further in, pull on any slack in the wires going to the Road Trip module to prevent them from getting snagged.
Engage Radio Locks: In the 2-inch gap, use a hook tool from your trim kit to pull up the sliding radio lock lever on each side. While holding the lever in the uppermost position, start threading the locking screws into place. This technique makes it significantly easier to align the screws with the locking mechanism. Tighten the screws just enough to hold them in place but allow the locking mechanism to still move.
Slide Radio and Secure: Push down on the locking screws to allow the locking mechanism to drop down slightly, but keep the screws engaged enough so they don’t fall out. This allows you to slide the radio fully into place without the locking mechanism obstructing it. Once the radio is fully seated and snapped into place, tighten the two locking screws at the top to fully engage the locking mechanism and secure the radio.
Antenna Placement: Observe the space between the two locking screws at the top of the now secured radio. This area often provides an ideal location to mount the wireless antenna for the CarPlay module. Use electrical tape to secure the antenna to the plastic trim in this area.
Reinstall Remaining Components: Reconnect the vent wire and reinstall the vent and vent trim piece. With the glove box still removed, carefully position the Road Trip module into the space between the glove box cavity and the radio, ensuring a snug fit. Orient the module with connectors upwards and the antenna wire downwards for a clean setup. You can route the USB port cable to poke out from the center console trim for easy access, with plans to refine the routing later.
Cabin Air Filter (Optional): While the glove box is removed, take this opportunity to replace your cabin air filter, as it’s now easily accessible. Simply slide the plastic tabs to release the filter cover and replace the filter.
Reinstall Glove Box and Trim: Reinstall the glove box, lower trim cover, and side trim cover in reverse order of removal.

Conclusion

Congratulations! You’ve successfully installed aftermarket CarPlay for your C250 Mercedes Benz, breathing new life into your car’s infotainment system. While this installation involves several steps, it’s a rewarding DIY project that significantly enhances your driving experience. Enjoy the seamless integration of your smartphone, advanced navigation, and hands-free convenience in your upgraded Mercedes C250.