I'm in the same boat (have a E90 330d)...
A diagnostics check showed all 6 glow plugs are not working so the control unit will need replacing as well as all 6 plugs... NOT cheap!!
is it advisable to get it sorted asap or can it wait as I thought glow plugs are only really used in Winter when its colder??
But on other hand have heard if not sorted can effect the regen process leading to DPF failure??