I found this. All the errors are generic to all models
Hi I'm a kenwood engineer
E4 means that the flood sensor located in the sump of the machine has got wet!
It only should get wet if the machine is leaking somewhere.
The sensor is designed to switch off the machine if triggered... To save flooding your kitchen!
Very good idea really - as most machines don't have this feature and flood the floor until the cycle is finished.
Yes you need to tilt the machine back to drain the water from the sump first.... Then look for your leak. The leak cud be on any hose or water pump... Or the seal under the filter chamber. Once leak fixed and water drained/dry
E4 should clear. Make sure machine is empty and unplugged before messing! :)
and can also be drain error
There is also a video on E4 errors.