Miele G646SC Plus dishwasher Drainage / inlet warning light

It could be a clogged in the drain line. Often the problem is at the point where the drain line attaches to the garbage disposer or household drain line. You should remove this line and clear it form any debris in the hose or the hose connection. Be sure to reattach the hose before starting the dishwasher again.
Good luck!

Mike from holland,
I know the answer ! And am very angry at a miele guy who came round for this same problem an year ago. Cost me over € 100,- or something. He fixed it then. But could ( or wouldn't) tell me what he did. He makes a living out of this. Sure he knows it. As a matter of fact, he didn't do anything worth mentioning.
Anyway. First offcourse clean the propellor. (see above) But then the software is still confused. And the light of the inlett/oulet keeps blinking red. So what I did was push two buttons at the same time. I can't recall which ones I pushed. So try different options. Let us know what the right combination is. But as a wonder the red light went out. It is working again.
So it has nothing to do with problems concerning waterflow. It is a software thing.

You can remove the sump filters and get to the pump impeller.
Bail out all the water, remove all the sump filters. You will see a wire clip in the sump, flick over the clip ( i think it's to the right) and grab the impeller cover and pull it upwards. There you will expose the pump impeller. Make sure there is no debris in there and the impeller turns freely. Stilk same problem, then make sure the main circulation motor runs. This you willl hear when the machine starts to fill. This is after the drain cycle. All Miele dishwashers drain first as soon as you press the start button in a wash programme.

I was called out for this very problem today. As a plumber, I found that the inlet water pipe was mounted vertically, I removed the straight through valve and fitted an elbow type so that the inlet sensor would sit horizontally - after weeks of failing in seconds, it completed it's cycle whilst I fixed a radiator problem elsewhere!

I had a Miele G646SC Plus With inlet / drain light coming on and no water coming into unit. All the above solutions tried. As with solution #6 removed the undertray to check the water leak protection float and microswitch. No water in pan,but found polystyrene float had distorted and activated the switch.I removed the float and sandpapered it flat.Switch function now operates and dishwasher is working fine. Hope this will be of help to someone

I had the same problem a few days ago. I followed the instructions to clean the filter and check to see that the impeller was free to rotate in both directions. The problem persisted. After reading this thread, and a similar one on another site, I tried what mikeboerma suggested in "solution #3", and bingo, problem solved. The magic combination is to push and hold the on/off button and the start/stop button.

I have a Miele G692 SCI Plus which had a similar problem a while ago.
The inlet/drain light also comes on when there is water in the base pan. There is a float switch that also triggers this and over time if water has collected in the base pan the float switch can stick. Pull out the dishwasher and tilt it towards to back. If there is any water in the base pan it will come out. To be thorough, put the machine on it's back and remove the base pan (4 screws by the feet), the float switch is a circular plastic casing with a polystyrene float in it. It comes apart for servicing, the float can jam if there is any rubbish in the water.

I had this problem, and cleaned the inlet and outlet filters, made sure the pump impeller spun freely, and tried all combinations of button presses. Resolved to try to make sure the outlet pipe was clear, I pulled the machine out from its 'semi-fitted' position, and found that a kink had developed in the outlet pipe restricting flow (it had been ok for the last five years!). Having straightened out and re-routed the pipe, the drain/inlet light now stays out, and the dishwasher works perfectly again!

Turn power off and count to 10.
Hold down Top Solo and start/stop button and push power back on.
You can select all programs now by multiple presses of the start/stop button.
Clean impeller on pump then I found filling up the machine with water for a while then a long drain cleaned everything without stripping out pipes.

miele g646 sc plus dishwasher the inlet/drain light stays on cant get rid of

I think that the pump impeller is jammed or clogged.