Did it come with a plug attached? Can you plug something else into the outlet you are using and see if it works? What model Miele? They seem to have the installation manuals available on their web site. If there is no indication of power on the unit, look carefully at the plug (unscrew it if possible) and at where the plug connects to the unit, someone may have pulled a wire loose while deinstalling it.

ronatalie,

Yes, plug is attached securely.
I have the install. manual and followed it to a "t".
No sleep, but up early to do some more investigating.
Disposal works on both receptacles. DW didn't. Flipped breaker switches, still no change.
Decided to use an extension cord and plug into a wall plug.
Guess what? POWER!
Any ideas as to what is wrong?

Thank you for your help!

Plug the extension cord into the receptacles where the disposal is plugged in. If the DW then works, there is an issue with the prongs of the DW not fitting the receptacle tightly. Bend the prongs of the DW plug out slightly and try again.

the receptacle for your disposal is switched I bet... If you plug your dishwasher into that receptacle and it isn't wired to have constant power there the dishwasher will only work when you have the switch on.

Unplug the disposal, plug the dishwasher in, turn the switch on, does it work? If so, in order to get it to work how you want it could be a lot of work and rewiring of the receptacle to turn it into a "half hot" meaning having switched power for your disposal and constant power for the dishwasher.

I bet hexus has it correct.

Depending on how the receptacle and switch are wired it could be simple to change, or could require a new cable from the switch to the receptacle (or even running a whole new branch circuit).

If the DW works with the GD unplugged, DW plugged in and the switch turned on, you need to turn off the circuit, then remove the switch cover plate.

If there are only two wires in the box (black and white) hooked to the switch you have a switch loop. This is pretty common since the GD is not allowed on the kitchen counter circuit.

If there is any other device in the box (like a receptacle) with the switch it gets harder to figure out what you have).

You could still have a switch loop, or someone may have wired the GD onto the counter circuit, or fed another circuit into the box for the GD.
If you have a switch loop, power comes from the receptacle box up to the switch for control, and then returns to power the receptacle.

This is easy to change so that half the duplex receptacle under the sink is always hot, and half remains switched for the GD.

Identify the 'always hot black' wire coming into the receptacle.

It is likely wire nutted to a white wire going up to the switch.

The black wire that returns from the switch should be connected to the brass screws of the receptacle.

You need to pig tail the 'always hot' so you can connect it to the other brass screw of the receptacle, and then remove the small tab between the brass screws.

One half of the receptacle is now always on, and the half fed by the switch will work as before.

Plug the GD into the switched half, the DW into the always on side.

If power is fed from the switch down to the receptacle, you will need another cable to bring an 'always hot; line down to the receptacle for the DW.

You also need to make sure at that point that the GD is not on the kitchen counter circuit.
It is not allowed to be, and the DW cannot be on that circuit either.

I haven't installed a Miele, but I believe they can be wired for 220v.

Yes! You are correct! Plugged in several appliances to see if they would work and no juice.
Couldn't figure out what was going on until I read your helpful posts!
The outlet is designed as you say and is to code specs for sure! Home is 7yrs old so I believe it's pretty current as far as wiring codes etc...
Will have to do some more probing as time allows to fix the issue, but most importantly is the fact that we now know why it wasn't working with the DW plug!

Many thanks for your expertise!