Understand the Problem
 

• Start by identifying any symptoms the vehicle is exhibiting, such as flickering lights, warning lights on the dashboard, or malfunctioning electronic systems.
• Check if the issue is affecting multiple systems or just one specific component, as this can help narrow down the cause.
• Take note of when the problem occurs (e.g., only when the vehicle is running, intermittently, or constantly).

 
Consult the Owner's Manual
 

• The owner's manual should be your first reference point when troubleshooting electrical issues as it contains valuable information about your car's electrical system.
• Look for any circuit diagrams, fuse box locations, and a list of fuses that can help you understand the system.

 
Inspect Fuses and Relays
 

• Locate the fuse box, which is typically found in the engine compartment or in the cabin, and inspect it for any blown fuses or faulty relays.
• Use the diagram in the owner's manual to identify the fuses related to the circuit or system experiencing issues.
• Replace any blown fuses with new ones of the same rating. If a fuse blows immediately after replacement, there could be a short circuit in the system.

 
Check the Battery and Connections
 

• Inspect the battery terminals for any signs of corrosion or loose connections. Clean the terminals if needed and ensure they are securely tightened.
• Test the battery using a multimeter to ensure it is holding a charge correctly. A fully charged battery should read around 12.6 volts or higher.
• If the battery is old or not holding a charge, consider replacing it.

 
Inspect Wiring and Connectors
 

• Visually inspect the wiring and connectors for any visible damage, such as frayed wires or loose connections.
• Pay special attention to areas where the wiring passes through the firewall or near moving components, as these are common places for wear and tear.
• Tighten or repair any damaged connections or replace wiring if necessary.

 
Utilize Diagnostic Tools
 

• Modern vehicles, including the 2016 Mercedes-Benz C-Class, are equipped with On-Board Diagnostics (OBD-II) systems that can help identify electrical issues.
• Use an OBD-II scanner to check for error codes which can provide insights into what might be causing the problem.
• Look up the meaning of any error codes retrieved from the system to understand which components or systems may be malfunctioning.

 
Consult a Professional Mechanic
 

• If you are unable to diagnose or resolve the electrical issue yourself, it may be necessary to consult a professional mechanic or an authorized Mercedes-Benz service center.
• Mechanics have the experience and specialized tools required to troubleshoot and repair complex electrical problems effectively.
• They can perform more advanced diagnostics and access any service bulletins that might relate to known issues with your vehicle model.