Fuse box Mercedes w203 - fusesdiagram Fuse box in passenger compartment Mercedes w203. fuse box location. The main fuse box is located in the passenger compartment on the driver’s side of the cockpit. Mercedes C Class w203 (2000 - 2007) - fuse box diagram Mercedes Class C w203 – fuse box – engine compartment Mercedes Class C w203 – fuse box – engine compartment. WARNING: Terminal and harness assignments for individual connectors will vary depending on vehicle equipment level, model, and market. Uncategorized Languages. English.