my buddys honda foreman 500 es after being rode for at least an hour or so will display the gear the machine is in and it will blink 3 times stop and blink 3 times continously unable to shift... when shut of and turned back on it will reset itself

any suggestions of what his problem could be

 

angle sensor fault. check the wires for corrosion at the sensor and ecu, if all looks ok and connectors are clean and tight, most likely a bad angle sensor. Might want to get a manual, it goes through all the steps for diagnosing. I could tell you how to go about it, but i have a rancher and the wire colors might be different.