E36 cabrio electric roof fault diagnosis

[JamesVFR]

Hi all
new on here
Just bought an e36 cabrio + the electric roof is not working
One of the hatch cables has snapped which i will order but there is no noise etc from the motors

Has anyone got a fault finding list as such so i can work through to sort the problem?
i cant even drop in manually as is seems that the motor pulls the cables to secure the hatch down + at the mo the hatch will just sit there un secured

all help appreciated
cheers

James