Honda Outboards BF40A/BF50A Service Manual, Page 331Get this manual
BF40A-BF50A 5) Connect the 12V battery positive terminal to the Brownwhite terminal and negative to the Blackgreen terminal for about five minutesA gentle puff of air should not pass through Note that inspection with the battery connected must be made quickly The SE thermal valve heater becomes very hot when the battery is connectedTake care not to touch it[1] BLACK! GREEN