Genuine BMW Wiring Harness Engine Grbx. Module - 12517593347: This is an OEM replacement wiring harness for the BMW engine GRBX. It is designed to replace the original harness that has become damaged or worn over time. This harness is made from high-quality materials and is designed to ensure a reliable and secure connection. It is compatible with a variety of BMW models and is a direct fit for easy installation.