mitsubishi heavy split fault

I have just installed mitsubishi heavy below cieling split system.
the unit is on a hard wired controller.
problem is the indoor fan motor runs for a couple of seconds the cuts out then starts straight back up again and repeats this process.
this happens in all modes
the unit sometimes stays on with no problem.
you can hear the relay on the pcb clicking as fan stops and starts.
there is no fault code on the controller
or irregular led lights on indoor or outdoor units.

strange one
can anyone help

What model is the indoor and the outdoor unit ?

Sounds like you have it set to heating mode, or in auto but calling for heat. The condensing unit will run, but the indoor fan will only run when the coil thermister reaches a certain temperature, if the fan is continuously starting and stopping, it is possible the refrigerant charge is short. Hope this helps. Regards, Andy C.

refrigerant charge is ok
only a 10m pipe run and no low pressure error code displaying
problem seems to happen in all modes
but intermittant, sometimes runs ok in cooling and heating

What is the model no.?

This sounds like an FDEN model unit that has been fitted with an RCE hard wired remote controller and the infra red receiver hasn't been disabled.
go to the discharge side of the unit and look for a light on the panel. if there is one or any numbers the unit still has the ir receiver connected so remove rh side panel and locate the 2 core cable going down length of unit in middle of which is an inline connector. Just pull this apart (with the power off!) and reboot system.
Brit

thanks
i spoke to mitsi technical before i recieved your message and they said the same
disconnect infa red sensor

not been back to site yet but im sure all will be ok

thanks for your help

its a easy job to do i had same problem ,its just the matter of snipping a wire on indoor pcb board to transfer from infa red to hard wired