I had the same confusion — you watch repair videos and expect to see a floor base with a float switch, but your Bosch dishwasher looks completely different. It feels like something is missing.
Quick Answer
On the Bosch SHXM4AY55N, the antiflood (float) switch is not exposed underneath like in some videos. It’s located inside the base assembly under the tub, and you may need to access it from below or the side.
Step-by-step guide to locating the antiflood switch
1. Understand what E15 actually means
The E15 error indicates:
- Water has entered the base tray
- The antiflood float switch has been triggered
So even if you can’t see it, the system is detecting water underneath.
2. Know where the float switch is located
On your model:
- The float switch sits in a hidden base tray (basin)
- This is under the dishwasher tub, not directly visible from above
- It’s part of the leak protection system
That’s why you don’t see a “floor” like in other models.
3. Access the antiflood switch
To reach it:
- Turn off power and water
- Pull the dishwasher out slightly
- Remove the bottom front kick panel
From there:
- Look underneath the unit
- You may need to tilt it slightly backward
Inside, you’ll find:
- A plastic base tray
- A float (usually foam or plastic)
- A microswitch
4. Check for water in the base tray
This is the most common cause.
- If water is present → it lifts the float → triggers E15
Fix:
- Carefully dry the base using:
- Towels
- Sponge
- You can also tilt the dishwasher slightly to drain water out
5. Inspect for the source of the leak
Drying resets the error temporarily, but you must find the cause:
Check for:
- Loose hoses
- Door seal leaks
- Faulty inlet valve
- Cracked sump or pump housing
6. Test the float switch
If no water is present:
- Locate the float
- Move it up and down manually
- Listen for a click from the microswitch
You can also test continuity with a multimeter.
7. Reset and test
After drying:
- Reassemble
- Power on
- Run a short cycle
If E15 returns, there is still a leak or a faulty switch.
Extra tips and best practices
- Always identify the full model number (e.g., SHXM4AY55N/24) for exact parts
- Take photos before removing panels
- Check for slow leaks that only appear during wash cycles
- Run the dishwasher while slightly pulled out to observe leaks
Common mistakes to avoid
- Assuming the float switch is missing (it’s just hidden)
- Resetting the error without fixing the leak
- Ignoring small drips that trigger the sensor later
- Tilting excessively and causing more internal water movement
FAQ
Why don’t I see a float switch like in videos?
Different Bosch models hide the antiflood system inside the base, not exposed.
Can I just dry it and keep using it?
You can reset it temporarily, but the leak will trigger E15 again.
Is E15 always caused by a leak?
Almost always. Occasionally, it could be a faulty float switch, but leaks are far more common.
Conclusion
Your Bosch SHXM4AY55N does have an antiflood switch — it’s just hidden in the base tray under the unit. The E15 error confirms it’s being triggered, most likely by water accumulation from a leak.
Focus on accessing the base, drying it, and then tracking down the source. Once the leak is fixed, the error should disappear for good.
Reference links
https://www.bosch-home.com/us/owner-support/get-support/dishwashers
https://www.manualslib.com/manual/1377207/Bosch-800-Plus-Series.html
https://www.repairclinic.com/RepairHelp/How-To-Fix-A-Dishwasher/52-6--/Bosch-Dishwasher-Error-Code-E15
