Mercedes CANbus Steering Wheel Control Interface With E-Call Retention

Upgrade your Mercedes audio system without sacrificing factory functionality using the 49‑MB‑05 CAN‑Bus interface. Designed to work seamlessly with aftermarket head units, this adapter retains steering-wheel audio controls, including volume, track skip, phone buttons, and the factory e‑call emergency system (where equipped). It’s ideal for maintaining safety and convenience features after replacing your original stereo.

The 49‑MB‑05 interface connects via the quadlock connector and includes a PRE‑15 ignition function, allowing the vehicle’s ignition to be controlled via the remote key—no ignition wire connection required. To toggle the PRE‑15 function, simply press and hold the PTT (push-to-talk) button for 15 seconds.

Key Features

• Retains steering-wheel audio & phone controls
• Maintains factory e‑call emergency function
• Supports aftermarket head units (patch lead required)
• Quadlock plug-and-play connection
• Includes PRE‑15 ignition feature (remote key control)

Wiring & Signal Outputs

This interface provides key vehicle signals for integrating your new stereo:

• Pink – Speed pulse
• Purple – Reverse gear trigger (+12V)
• Green – Parking brake signal (−12V ground)
• Yellow/Black – Mute signal when reversing or if PDC (Park Distance Control) is active

These outputs help support video lockout, camera input activation, and reverse mute functions on compatible head units.

PLEASE NOTE: A dedicated 49-Series patch lead MUST be ordered with this product. This links the steering control interface to the steering wheel control input on the back of the new stereo