Ever since the sun pannel was installed I had the suspicion that it was not working correctly. To find that out I had Camperprofi in Veendam add a Voltmeter to the system. This showed that the fuse, even a 30A, blew out. When and why? The power source had to be the camper battery. The MPP regulator short circuits the battery when the car’s dynamo charges the battery to above 14.2 V during long drives. The German manufacturer admitted that there was a software fault in the converter so I had it changed out. Problem solved (?, to be confirmed).
Following the installation of the larger tires and the Seikel lift kit, by The VW Store in Assen, the car drives a lot better. The noise level and fuel consumption has however increased. There is also now and then a scratching noise which suggest something is touching the rotating wheel on the left rear side. The car is now at the garage to solve this. It appeared to be the front wheel pressure hoses of the breaks which touched the wheels. That was solved.