Set Appliance State:

Ensure NO demands
WARNING! - Mains voltage is expected during test follow
TOPs P4 live testing procedure
Mains Power On

Observation:

For information on how to access d.96 refer to ADAPT.
Once you navigate to d.96 change the setting from '0' to '1' then confirm adjustment.
This will force the appliance to perform a factory reset.
Does the appliance now enter standby or does the fault code remain?