Mast is stuck in the air, tilting downwards. Have mechanically released the valve to lower the mast (to fit into our unit) but will not lower using the joystick controls. Joystick works for everything else. When going to lower the mast, engine goes under load but will not lower.

No fault code displayed on the dash.
Have fitted a new control unit which has made no difference.
Unload valve and key off lift lock has been checked, no issue found.
All fuses and relays checked, no issue found.

We have been through the oil control valve & mast sections of the manual, which haven't provided any clues...The company we use for diagnostics has said they are unable to help!

Does anybody have any advice, or know where we can source diag equipment/a technician? We are based in Plymouth, England.

Thanks in advance!!