2002 Yamaha YFM660 Grizzly factory service and repair manual, Page 388Get this manual
SIGNAL SYSTEM 8.If the differential gear lock indicator light LED fails to come on: 1.Differential gear lock indicator light
Check the LED of the differential gear lock indicator lightRefer to "CHECKING THE LEDs"CONTINUITY
NO CONTINUITY
Replace the meter assemblyNO CONTINUITY
2.Four-wheel drive switch Refer to "CHECKING THE SWITCH"CONTINUITY