C70 hard top open process stops half way

[BertoneP]

Hi,
I own a C70 MY2008 with the 2.0d engine since 2012 and have had no issues at all with the hard top. All worked well until 6 months ago when an intermittent problem with the roof started....

The problem is that when I open the top the process starts correctly, i.e:
all 4 windows lowers a bit, the boot lid opens up, the roof detaches and folds down into the trunk...then it suddenly stops working and a warning sign is shown on the dash.

The top stops in this position (see attached picture).

To fix the issue I remove the negative lead of the battery and leave the car for about 30 min without power. Then I connect again the negative cable to the battery, turn on the ignition and press the close button of the roof and then the roof starts moving and closes without any problem.

I can then repeat the open and close process several times without any issues.

I believe there could be a probem with some hall sensor of the roof but Im not sure....has anyone resolved a similar problem ?

Thanks for your help!