After some difficulty I found and extracted a blown fuse 40. The old one was 20A. Is this actually correct? The handbook only tells me to replace with the same as extracted.

Yep. 20A.

Any idea why it blew?

Replaced it and seemed ok. Then plugged in my phone charger, ok at first and pop again at the second usage. A pain but will get some more fuses and try other items like an electric tyre pump to eliminate items.

Check your phone charger wire or the if its a usb connection is not damaged.

Edited 31 January, 20179 yr by BATVANVRS

9 minutes ago, BATVANVRS said:

Check your phone charger wire or the if its a usb connection is not damaged.

Second that, there's no way a USB charger should blow a 20A fuse.

After replacing the fuse a number of times, the problem seems to be the plug in charger. Even when no lead is plugged in, it blows the fuse when the charger is moved slightly. I have contacted the supplier and will wait for a reply before giving out details. Meanwhile I can use the cars USB connector which has a lower output .

OK, can not contact the supplier- I bought it via Amazon.

The charger looks good ,is gold and white is branded RUNSHION and marked Qualcomm Quick Charge 2.0. As I said it blows a 20A fuse when moved around slightly in the socket. A cheaper and less powerful charger does not cause the same bother.