Maestro Dimmer 3-way always on

[pavon]

I'm replacing an existing 3-way switch pair with an MACL-153 and MA-R dimmer switches. I wired everything up according to the instructions, but when I turn the power back on, I measure 120V at the light fixture all the time (currently nothing connected). Pressing either button does nothing. I thought it might need programming so I held the T and R buttons on the MACL for about 30 seconds and none of the indicator lights turned on.

I disconnected everything (except the green grounding screws), and measured voltages of all other wires relative to ground on both ends. As expected, the black wire which I had connected to the black screw on the MACL-153 was the only one with power. I reconnected just that wire to the black screw on the MACL-153 and I measure 120V on both of the other screws and this doesn't change when pressing the button.

Any idea of what could cause this behavior, apart from a defective unit?

Also, is there a document describing the expected behavior (voltages on different wires in different states) to use for general troubleshooting (presuming these work differently from regular 3-way switches).

[pavon]

Oh, after powering off and disconnecting everything I also ohm'd out the other two wires to verify that matching ends had been connected to the blue and brass connectors respectively.

[pavon]

Nevermind. Looking through the Troubleshooting FAQ again, we noticed that the switch needs a load to operate. After connecting the light fixture everything works fine.