Sorry if i sound stupid, but the dark grren wire you are talking about is the one of the 3 plugs that has the solid green wire? One of the plugs has a green wire with a white stripe and the other has the solid green wire. This is the one you are talking about?
The schematics show 3 connectors.
1) High pressure cut out switch is two Black wires.
Switch opens when AC pressure reaches 430psi.
2) Low pressure cycling switch (evaporator tube)
DarkGreen/White wire and a Black wire.
3) High pressure fan switch. (for some unknown reason
the manual shows it as high pressure switch). Other
manuals call it a fan switch. Switch opens at 233 psi
and closes when pressure is below 180 psi. When the switch is closed a ground is placed on pin D11 of the ECM. When
the switch opens the ECM responds by turning on the radiator fan. The connector wires are Dark Green wire and a Black wire.
This is the switch that must be causing the fan to come on.
The only thing I can think of is the connector pin for the
Dark Green wire is damaged inside the connector plug.
So I recommend you use a razor blade and cut back
some of the wire insulation from the Dark Green wire a
couple of inches in back of the connector plug wire.
Then attach another wire to the exposed wire and the other end to the negative battery terminal.