My son has a 2008 Suzuki King Quad 750. We were out this past weekend & noticed that the 4X4 was not working. The 4X4 indicator was on, but it was only in 2 wheel drive. When he pushed the 4X4 button on and off, it didn't make any difference. The 4X4 indicator stayed on. Also, when he put the front diff lock on, all it did was "flash" on the screen. I believe it may be something electronic, but not sure. Anyone have similar problems or know what it may be. Thanks.    

check the connectors and fuses, if seated and good . If they are, you may have a bad front accuator, common if the 4WD lock is engaged with the wheels cranked.