This is all I can find on your problem hope it help's.
Fuel Sedimenter Switch
1. Check that there is continuity between the switch connector terminals when the float in the fuel sedimenter is above the water drain line.
2. Turn on the ignition switch, remove the fuel sedimenter connector, and connect the terminals of the connectors on the harness side. Confirm that the sedimenter warning lamp lights up.
If abnormalities are detected during the check, replace the switch parts and carry out repairs in case of defective connection between circuits or short circuits.