The control panel on my dishwasher is showing a tap and E15

This is a flood sensor issue rather than a float switch issue. The sensor is in the tray and senses water from dripping hoses or worn pump seals. It doesn't need much water as the sensor is at the lowest point, so it only needs a teaspoon of water. you can check the connections at sensor end and follow it to the control board connector.

My Bosch Dishwasher is displaying an error code E15, what does it mean? An E15 error code indicates that the safety switch has detected water in the base of the dishwasher. Your leakage protection system has activated.

E15 Bosch Dishwasher Error Code

Videos as well with fixes

https://www.google.com/search?q=bosch+dishwasher+has+a+E15

..

Not all dishwasher work the same way. What kind is yours?

First you have to fix where the leak is coming from that tripped to E15 error code. You can reset by turning off power for 15 minutes.

An E15 error code indicates that the safety switch has detected water in the base of the dishwasher. Your leakage protection system has activated. What can I do to fix the E15 Error Code on my dishwasher?

E15 Bosch Dishwasher Error Code

.https://www.google.com/search?q=dishwasher+e15+error

...

E15 is a leak into dishwasher base. Leak can be as simple as using to much soap powder or a split lower spray arm to more expensive fix of a leaking sump base or wash pump. Need to pull dishwasher out of cavity, remove side panels and front kick panel and run machine and watch base to see where leak is coming from. Have had them leak from 4 main places. Heat exchanger where large plastic nut screws from inside. Bottom of wash pump. Plastic sump base (mainly towards front of machine. And last place is a small pin hole can develop in stainless base of machine towards front of dishwasher. Check soap usage and lower spray arm for splits first.

You need to unplug the machine, take it out and take the top and side panels off.
Remove the water from the base of the machine, then, plug in and set it going.
Watch it working and check to see if it's leaking.

The overflow switch has been activated.
It means that its a internal leakage.
Unscrew the side panels or frontpanel under the door and dry out the water with a towel and test the machine.
Check for leakage.

Most likely it is the flood switch trigger causing the problem.
Many reasons for this but mainly it means there could be water leaked into the base of dishwasher where flood switch is located.
Or if you have Aquastop fitted in the water inlet hose then the hose might have kinked due to age or being pressed between cabinet wall and dishwasher. Turn power off to dishwasher at mains plug and pull it out. Check hoses. Tilt it about 20 degrees to one side on a towel and hold for about 10 secs. This should get the water out. Wait an hour or so to dry any moisture in the base and then plug back in and turn on. This should reset the E15 fault.

try to disconnect the power cord or turn OFF the breaker circuit controlling the dishwasher, for to reset the problem. If the problem appear check the troubleshooting section in your owner manual download from www.retrevo.com or www. manualslib.com and fix it.

Merry Christmas.

I'm going to assume this is an SMS GV640 bosch, E15 indicates there is water in the base under the tank and therefore a leak. Pull the front of the machine onto a towel and pivot the whole machine forward (ie lift the back off the floor at about 45 degrees). If you see water flow from under the machine, you have a leak. You may find the the machine will now seem to work, but you will have to trace the leak or it will activate the flood device and give you E15 again.

E15 indicates the anti flood device in the base of the appliance has been activated.

Unplug the appliance.
Take the cover below the door off.
Take the insulation out of the way.
Remove any water in the base that is lifting the float.

Once removed, try the appliance again. Watch through the open inspection panel to see if the appliance is leaking.

If the float isn't up activating the switch then the switch, wiring or control board is faulty. Check the float and check the switch.

Your machine is still under warranty so you do need to be careful about what you do.

Trying to repair it on your own may invalidate the warranty.

Hope helps.