Cause : Speed Reference Missing comes when parameter d1-18 is set to 3, leveling speed detection is not assigned to a digital input (H1-XX not equal to 53) and no speed was selected while an Up or Down command was entered.

1. Parameter d1-18 is set to 1, H1-XX is not set to 53 and no speed was selected at start.
2. Make sure the selected speed selection method matches the elevator controller sequence. Check parameter d1-18 and H1-XX settings.
3. Make sure the elevator controller is connected properly.
4. Make sure the elevator controller selects the speed properly.