2003 Yamaha YFM400FAR Kodiak Factory Service Manual, Page 105Get this manual
ADJUSTING THE REAR BRAKE LIGHT SWITCH CHECKING THE FINAL GEAR OIL LEVEL
2.Adjust: Rear brake light switch operation timing
the main body of the rear brake light switch so that it does not rotate and turn the adjusting nut in direction or until the rear brake light comes on at the proper timeDirection Direction Brake light comes on soonerBrake light comes on later