Roof won't raise or lower

[Jim86]

Hi all,
The other day I put the roof down, drove for an hour or so and parked up. Couldn't get the light to illuminate on the dash to say it was ready to raise/lower.

This is what I've observed and done so far:
1. Disconnected the roof mechanism and raised it manually.
2. Swapped microswitch in the latch for a brand new one. No difference.
3. If I unlatch/latch the roof and the windows are up, nothing happens. If I unlatch/latch the roof and the windows are down, they rise to the top.
4. Handbrake light DOES come on when handbrake is engaged.
5. I can find no sign of relay clicking or any other sign of life from the system.

If anyone has some thoughts, that would be great. I'm thinking relay next? I have a friend with a 986 who I can visit in December so I might be able to try his relay then.