2006 Honda TRX680 Rincon Factory Service Manual, Page 147Get this manual
FUEL SYSTEM (PGM-FI)
MIL CIRCUIT INSPECTION
If the engine can be started but the MIL does not come on with the ignition switch ON and engine stop switch "O", check as follows: Check the various functions of the combination meterIf they do not function, check the combination meter power input line (page 23-8)If they function properly, check as follows: FA model shown: MIL
Turn the ignition switch OFFDisconnect the PCM 33P (Gray) connector
Ground the Whiteblue (B19) wire terminal of the wire harness side connector with jumper wireTOOL: Test probe 07ZAJ-RDJA110