To edit fuel consumption rates ('Consumption by rates' section on the Fuel Consumption tab):

svc=unit/update_fuel_rates_params

Parameters:

{
	"itemId":<long>,		/* unit ID */
	"idlingSummer":<double>,	/* idling summer, litres per hour */
	"idlingWinter":<double>,	/* idling winter, litres per hour */
	"consSummer":<double>,		/* summer consumption, litres per 100 km */
	"consWinter":<double>,		/* winter consumption, litres per 100 km */
	"winterMonthFrom":<ubyte>,	/* winter month from */
	"winterDayFrom":<ubyte>,	/* winter day from */
	"winterMonthTo":<ubyte>,	/* winter month to */
	"winterDayTo":<ubyte>		/* winter day to */
}

Return value:

{}	/* OK */