When turning on dishwasher it just fills the base with water, tried manually draining and pressing reset buttons to no avail

It means there's water in the base which has activated the flood detection system.

Have you unplugged it for about 20 minutes yet and tried again?

The manual shows there are 3 possible causes of the alarm
1. water supply is not there
2. drain time is too high - possibly a blockage in the kitchen sink drain
3. the water overfill in the base.

Most likely the cause could be 2 or 3. If kitchen drain is clear then the reason could be a faulty overfill switch at base of dishwasher assuming there is no water collected at the base where the motor and pumps are located.

There might be water in the base. take the cicker off and open the small access door ...2 screws.....if there is water in the base soak it up with some rags or a sponge and try it. if more water come in the base there is a leak somewhere. Then you will have to remove the base to investigate....good luck

Hi
If clean light is blinking 7 times then it may be an issue with heater circuit, door switch or wash pump. If yes then please reset the power to the dishwasher. After, 5 minutes check if you are still getting the same error. If yes, then it is a water heating fault. To resolve this error try pressing this reset sequence-- Heat Dry - Normal - Heat Dry - Normal or High Temp - Air Dry - High Temp - Air Dry or Hi Temp Scrub, energy saver dry, Hi Temp Scrub, energy saver dry. Now let the unit run for 2-3 minutes and then you press the Cancel/Drain button and allow it to completely drain and reset.
If this doesn't work then it's an issue with the wash pump not pumping the water past the heater efficiently or due to lack of water to heat. Please make sure that heater is not open circuited and is heating the water efficiently. You'll have to check the heater using a multimeter; the meter should read between 3000 to 3300 ohms (Use multimeter on Rx1 ohm setting). If heater is fine then make sure water pressure is optimum and fill valve is working fine. Hope this helps... Please post back for further assistance.

Hi there.this is (over fill error).It has over filled & flooded water down into the base.It has tripped a flood switch in the base wich turns the drain pump on even though the washer is off.You can simply try tipping the washer to get the water out or you will need to disassemble the front kick panel at the bottom front to mop out the water.The switch will reset after you do this.Or wait a couple of days and the water will evaporate enough that the pumping will have stopped & the washer should work again.The booklet for your washer has water hight level settings in it.Sometimes someone leans against the washer and presses the buttons wich changes the water level to high & thats why this has probably happened in the first place.It may need setting to a lower level.

On bosch dishwasher if the base senses a water leak the unit will not fill & the drain pump will come on. I recommend checking for water in the base & locating the source of the leak if you see water in the base. Other possibilities; fill switch, water level switch or water valve. There is no reset for this problem.

most bosch have the inlet valve at the end of the fill pipe and it has an anti-flood device.
try turning off the water, take off the fill pipe then reconnect it and see if this works.
taking off the fill pipe resets the anti-flood device

In the user manual there's a section on how to clean the non-return valve. It's the plastic piece under the wire below the triple filter. Why did you pull out the machine? Did you kink the drain hose? If you don't find a clogged valve, spin the impeller wheel several times. It's under the valve inside the bottom hole where the valve came out.
Now here's the important step- Reset the fault! Power off/on the unit. If the light blinks when you turn it on, Press and hold the start button 4 seconds with the door open. Find the combination of off/on buttons to press to reset the machine in the user manual.
(Note: If the machine runs continuously as soon as you pressed on the power button, then you have water under the unit in the safety pan. Call Miele for help.) Now select the normal wash cycle close the door and start it. The drain motor always runs first. This verifies to the brain how much water is inside the machine when it starts filling. The drain pump runs for half a minute. If you hear it running with no drain check the drain hose especially if it's connected to a disposal. Clean the disposal.. If it's not running at all the light will go on again before filling, call Miele. If the machine fill up with fresh water, the drain works. Watch and listen when the light comes on. Is it filling or did it start circulating? Open the door, are the baskets are dripping wet? Then it filled and circulated. If the light comes on several miutes later then call Miele.

that usually happens when there is water in the base of the dishwasher where the motors are. Check to see if there is water in the base. This will trigger a float that turns off the water and on the drain pump.Remove the water and it should fill. However note that water came from somewhere, so find where it is leaking.