I know this is YEARS later, but thank you so much for the advice, i also had the problem of the boot not opening, and this procedure cleared it up perfectly. PS. problem was probably caused by two people pushing the two roof buttons at the same time
the common-sense solution was simply to splice the loom and fix the broken wires locally, but that this would leave them (the dealer) at risk of getting any future warranty claim refused if the same problem cropped up again.
This worked perfectly! No fuse or battery problem. Was cleaning my car inside with 5 year old daughter playing on the back seat with roof open. She must have leant on the open roof, and left it in an 'open' state. Same issues as described in this forum. The reset has stopped me panicking, and a big apology to my daughter (chocolate covered).There is an extra 12 page manual for the 500c, which should have been provided. Have a look through your documents in case you've missed it - it's just a thin leaflet so easy to overlook.
Instructions for the roof re-set are as follows:
Initialisation Procedure
The soft top must be re-initialised after disconnecting the battery or if the relevant protection fuse is blown (which I guess has happened to you?).
Proceed as follows:
make sure the motor is running during the whole initialisation procedure
keep the opening button pressed until the soft top is completely open
when the soft top is completely open, keep the button pressed for at least 2 seconds
keep the closing button pressed until the soft top is completely closed
when the soft top is completely closed, keep the button pressed for at least 2 seconds
When the procedure is terminated, the soft top will automatically carry out a complete opening and closing cycle (up to 25 cm from the completely closed position) to inform the driver that correct operation has been restored.
Hope this helps!
If I had to guess would say roof goes back so far so doesn't damage spoiler or the boot so the boot can be closed if the roof fails. What engine has your new project got, as a Twinair convertible would be a lot of fun with roof down and cold aircon. 1.2 lovely engine, performance just isn't the same though.