When your 2001 Toyota Corolla has a burnt-out headlight bulb, it reduces your visibility in the dark. Failed headlights also reduce the ability for other drivers to see you on the road. Always replace a headlight bulb as soon as it fails. The 2001 Corolla uses bulb No. 9006 for the low beam and No. 9005 for the high beam. You can buy the bulbs at any auto parts store or Toyota dealership.
Raise the hood of your Corolla, and rest the hood on the support rod to keep it out of the way.
Locate the wiring harness connected to the headlight bulb just inside the Corolla's engine compartment. Pull the wiring connection straight off the back of the bulb while pushing in on the locking tab.
Twist the retaining ring counterclockwise to remove it from the bulb assembly. Pull the bulb assembly back out of the headlight compartment. Twist the bulb counterclockwise to remove it.
Disconnect the socket from the rear of the bulb. Press the retaining clip and pull the socket connection straight off the bulb.
Press the bulb into the socket until the spring clip clicks to let you know it is secure. Insert the new bulb into the headlight assembly, and turn it clockwise to secure it in the assembly.
Replace the retaining ring, and turn it clockwise to hold the bulb in place. Press the wiring harness into position until it clicks.
Repeat the process on the opposite side. Test your Corolla's headlights to be sure they function properly.