marker lights out

If the marker lights on your 2003 Mercedes-Benz SL500 are out, despite the bulb appearing to be in good condition, there could be a few potential reasons for this issue: 1. Fuse: Check the fuse box for any blown fuses related to the marker lights. A blown fuse can cause the lights to stop working, even if the bulbs are fine. 2. Wiring issue: There might be a problem with the wiring or connectors that supply power to the marker lights. Damaged or disconnected wires could be the cause. 3. Faulty switch: The marker light switch might be malfunctioning, preventing the lights from turning on. 4. Control module problem: Modern vehicles often have electronic control modules that manage various lighting functions. A fault in the module could lead to the lights not working. Given that the problem has persisted for six months, it's essential to have a qualified mechanic or technician inspect your vehicle. They can perform a detailed diagnosis to identify the specific cause of the marker light issue and recommend the appropriate repairs. Electrical issues can be challenging to diagnose and fix, so it's best to rely on a professional with experience in Mercedes-Benz vehicles to avoid any unnecessary expenses or further complications.