1998 to 2004 BMW 3-series compact sport luxury sedans are built on a platform called the E46. The E46's front end was engineered to allow you to remove the headlight without having to take off the grille or the bumper. For this reason, no special tools are required and the entire job should take you no more than an hour. If one of the headlights on your 1998 to 2005 BMW's 3-series has failed or is damaged in any way, you can remove it yourself and potentially save a bundle of cash you'd otherwise give a mechanic or a dealer service department.
Turn off your E46 BMW. Prop open the hood with the hood support rod.
Remove the four 8mm bolts securing the headlight assembly to the front end of the E46. Two of the bolts are on the front portion of the top of the headlight. The third is at the rear of the headlight. The fourth is on the grille side of the assembly.
Pull the lower headlight trim off the headlight assembly. Press in with the flat end of your flat-head screwdriver on the tab securing the trim to the housing on the grille side of the assembly. Pull the trim toward you while standing directly in front of the headlight. Put the towel around the flat end of the flat-head screwdriver and press the head into the gap between the fender and the trim while pulling the trim toward you. It should come swiftly out.
Slide the headlight toward you until you can easily reach the wiring harnesses on the rear of the headlight. Remove the three wiring harnesses on the rear of the headlight by pressing in on the side tabs of each headlight and pulling.
Pull the headlight out toward you and wiggle it side to side until it is completely free of the front end of the E46.
Repeat this process for the other headlight on the E46, if necessary.