1989 Honda FL400R Pilot Service Manual, Page 241Get this manual
LIGHTSSWITCHES COOLANTFUEL WARNING SYSTEM NOTE
When the igndtion switch is turned ON, the fuel reserve and coolant temperature indicators should come on for few seconds then go off
Indicator does not go off (coolant temperature is low and full of fuel) INDICATOR COMES ON
1Disconnect the timer unit and sensor connectors and turn the ignition switch ONINDICATOR GO OFF
short circuit in the wire (Fuel: GrBI, coolant GBu)