##  **What to do if the Mercedes head unit does not turn on? (Mercedes Vito / Viano / Sprinter radio power issue / CAN-bus wiring fix)**

### Symptoms:

After installing a new Android head unit in a Mercedes-Benz vehicle (such as Vito, Viano, or Sprinter), the stereo fails to power on, the screen remains black, and the device receives no ignition signal (ACC) because the factory CAN-bus communication is not properly established.

### Solution:

To resolve the power issue and successfully boot up your head unit, check the wiring harness and follow these steps:

* **Check CAN-bus Connectors**: Inspect the main wiring harness, as it features multiple CAN-bus connectors designed for different vehicle configurations or equipment levels.

* **Switch the Connector**: Disconnect the current plug and connect the alternative small CAN-bus connector to ensure proper data communication with the vehicle's electrical system.

* **Verify ACC Power**: Once the correct CAN-bus line is engaged, the decoder will successfully issue the 12V ACC signal required to power on and start the head unit.

For a visual demonstration of this wiring fix, follow the instructions in the video guide: [Video Tutorial](https://youtube.com/shorts/XYL93MTfpF0?feature=share)

### Keywords:

Mercedes head unit not turning on, Vito Viano Sprinter radio power fix, CAN-bus connector wiring, Android stereo no power Mercedes, ACC 12V issue, SMARTY Trend installation troubleshooting.