Insteon dimmer switch 2477D not working.


New Member
The switch acts like it's on, but lights don't work.  Switch LED's are on.  App connects to it fine and even turns it on and off like normal, yet no lights.  I have done all the updates, resets, reinstalls that Insteon recommends.  Even use the gap switch to reset.  No result.
The switch that was there before works perfectly fine.  So does the light fixture.  I have tried this with 2 different Insteon switches and the result is the same.
My wall has 4 wires:  red, black, white, and ground.  I determined with a meter that the line wire is the red; so I switched the red and black wires.  But I have tried it both ways.
Please help this frustrated DIYer......
radrzr said:
radrzr, on 03 Oct 2021 - 19:47, said:
The switch that was there before works perfectly fine. So does the light fixture. I have tried this with 2 different Insteon switches and the result is the same.
Are you saying that you've tried 3 switches, and the 2 most recent switches both work, and only first one doesn't?

If that's the case, from your description, I would suspect a failed triac.
I would rig up a test using a power cord and light bulb to test the switch and confirm it works. Then you can proceed to troubleshoot what is different about the location you are installing it into. I have seen some strange issues with Insteon sometimes, they usually involve a GFCI socket in the circuit someplace. First step though is to be absolutely sure the Insteon device is actually working.
Are you sure that this isn't the end point of a three-way circuit?
If so, two of the wires are travelers & will alternate which one is hot when the other switch in the three-way circuit is flipped.
Be careful.
To test the switch:
I do this today with WiFi, UPB, X10 and used to do this with Insteon switches.
1 - take an old computer cord (3 wires) and strip the computer side off and connect the wires to the switch (Neutral, Hot and ground).
Leave the line wire and neutral wire uncapped and use a VOM to test the line and neutral leads when you press the switch.  Be careful doing this.
2 - check the line leads to lamp with a VOM to see if the switch is working.
Wires in box:
My wall has 4 wires:  red, black, white, and ground.
This is sort of normal when box is controlling a lamp and the box is the source switch for the lamp. 
Old wall light box switch methodology was just a hot and line lead to switch in box and a traveler if it was in a 3-way circuit.  
Typically here my light switch boxes use black for the hot lead and yellow, blue or red for the line lead or traveler wire to another switch or to the lamp box or outlet.
Well too if it is in a 3-way circuit then the traveler here is yellow or blue.  Depends really on the electrician that installed the wires.
You already tested the red wire to be hot.  Now test the black wire to where it goes for the lamp whether it is a ceiling lamp or wall outlet.
White is typically neutral and you will should see white wires in your fuse panel for neutral.  
Ground is ground.  It could be a bare wire or a colored green wire sometimes.  If the box is metal then a VOM will show the connection of white wire or ground wire to the metal box.