Light bulbs burn out on BMW lights, but replacing the bulbs is a relatively simple procedure that does not require tools. The process should not take more half an hour. It is recommended that you perform this replacement in your garage or driveway to avoid in dangers associated with street-side car repairs.
Park your car in your garage or driveway and turn off its ignition. Open and secure the bonnet on your 3 series by pulling the bonnet latch under the steering column.
Locate the rear of the headlight assembly in your engine bay. It is a concave plastic housing at each front corner. Rotate the housing left with your hands, being careful not to touch the engine if it is hot. Remove the housing and place it to the side. Rotate the bulb cage under the housing to the left and pull it out.
Pull the old bulb out of the housing by hand or with a gloved hand, if the bulb was previously illuminated and is hot. Plug a new bulb into the housing.
Reinstall the bulb cage and rotate it to the right to tighten. Reinstall the housing and rotate it to the right to tighten.
Do not perform this procedure while it is raining as water can become trapped inside the light bulb chamber.