Identifying single pole wires for smart dimmer

[Shawn B]

This should be simple...
Master bedroom has a single pole switch leading to a new and perfectly working fixture. I'm trying to install a Feit smart wi-fi dimmer for it. The switch box contains a top cable with a black, white, red & ground wire and a bottom cable with a black and white cable. The top and bottom white wires are tied together. The Feit dimmer requires a neutral. I've connected the top black to the switch load, bottom black to line, both whites to neutral and ground to ground. This powers the switch LED's but does not turn on the fixture. What am I doing wrong?

 

[littlespark]

Can you post a photo of the connections and where the coloured wires go.

@Megawatt should be able to advise better as this is a mainly UK forum, although we do have members from around the world.

 

[Megawatt]

This should be simple...
Master bedroom has a single pole switch leading to a new and perfectly working fixture. I'm trying to install a Feit smart wi-fi dimmer for it. The switch box contains a top cable with a black, white, red & ground wire and a bottom cable with a black and white cable. The top and bottom white wires are tied together. The Feit dimmer requires a neutral. I've connected the top black to the switch load, bottom black to line, both whites to neutral and ground to ground. This powers the switch LED's but does not turn on the fixture. What am I doing wrong?

The cable with the red is probably the switch leg or could possibly be the black also in that cable

 

[Shawn B]

Hello again,
So as mentioned above there are 2 cables leading into the box, as there should be; one from the top and the other from the bottom. Top cable has all 4 wires, bottom has black & white with this black carrying live power. The FEIT dimmer can be installed as either single pole or 3-way as long as there's a neutral wire. This is a single pole installation and there is a neutral wire (which I believe are the top and bottom whites. The dimmer instructions aren't entirely clear (to me), but show a single pole installation with line, load, neutral & ground connected (which I have as outlined above). Single the switch is receiving power (the LED's are lit), neutral must be correct, and single my meter is only showing the bottom black as live, that should go to the line terminal on the switch. That leaves the top black to connect to the load terminal. Capping or connecting the top red to the YL/RD switch terminal does nothing- the fixture doesn't turn on. Help?