Mass transit advocates tried without success Wednesday morning to purchase MetroCards with IOUs to protest what they said was the state’s failure to fully fund the Metropolitan Transportation Authority’s capital program.

Members of the Riders Alliance and Straphangers Campaign presented their IOUs at the Bowling Green stop of the Lexington Avenue subway line.

“The IOU doesn’t work,” Macarthney Morris, 33, of Astoria, said as he tried to slip his protest sign into a MetroCard vending machine.

The protesters then crossed the street to testify at the monthly meeting of the MTA board.

The state plans to contribute $7.3 billion toward the remaining four years of the MTA’s 2015-2019 Capital Program, but Gov. Andrew M. Cuomo has said he will release the money only as it becomes needed.

Cuomo has said through spokespersons that the state will meet its commitment to the capital budget, which funds long-term projects such as the Second Avenue Subway and the purchase of new buses and subway cars.