So there's 3 elevators in a triplex, M, 2, 3.

For some weird reason, lift 3 will sit on the lowest level and not respond to landing calls, and not return to it's parking level (ground floor, the level above)

There's no fault showing on in the fault log.

I have swapped the Ebcom grouping board with lift 2 previously but this has not transferred the fault.

I am sort of lost for ideas on how to further investigate this issue. I can give the elevator car calls from the smlcd and it will respond to it and sort of 'wake up' and will start operating correctly, responding to all landing calls.

This only seems to happen on the lowest level.

Any ideas would be greatly appreciated