Posting on behalf of a friend he has no low box hehas changed ecu and ratio motor and still.nothing any ideas please

Manual?

Sorry auto

Is neutral is being shown as selected when gear stick is moved to central position?

Yes it is

He gets the beeping and the cogs from dash it's shows up as neutral on the gear change and diagnostic

It's worth checking the connector at the motor to make sure it is getting 12V to try and move it.

If you know the ECU and the motor are good, and it acts like it wants to shift to low range, then check and see if there is 12V at the motor connector. If there is, then maybe the mechanism is jammed and it won't shift. If there isn't 12V, then may be work doing some digging, as there is a connector under the centre console (which is a bit of a pain to get to) but I've had a couple of owners who have found it to be a bit green and cause issues with the transfer case shifting - or giving a 'select neutral' message when it shouldn't.

It's the only other connector in the loom between the ECU and the motor - so if they are known to be good, then it's work checking it. You can also check the continuity along the length of the wires between the ratio motor and the transfer case ECU.
You can also check to make sure the mechanism will shift OK - without the motor on, you should be able to manually turn the stub anti-clockwise with a pair of pliers to move it to low range. If that works, then the problem is definitely electrical

Thanks marty il let him know