E1 points to the drain system in the documented Toshiba top-load AW-E900LM. Check the discharge path without copying the height setup from a front-load model with a pump.
The match is confirmed on page 18 of the official AW-E900LM manual. A chart that assigns E1 to water intake should not be applied to this reference.
Check the hose with the machine stopped
See whether the hose is installed according to the manual, bent, crushed, or externally blocked. Also check whether its end is submerged and whether it has been exposed to freezing temperatures. A hose that appears clear along part of its length can still be restricted at the end connection.
Respect the model’s discharge design: raising the hose to mimic a pump-equipped installation can prevent draining. Do not remove the valve or drain motor.
On the AW-E900LM, after correcting an external condition and with the drum stopped, the manual says to open and close the lid once and press Start/Hold to resume. If E1 returns, request service; do not keep trying to spin with water still inside, and do not open the appliance to check internal components.
Describe how the hose ends and whether there were any installation changes; that helps assess the correct drainage of this top-load model.