Just checking over Motorhome and found leisure battery absolutly dead no electrics in habitation area and control panel not working. It was all ok last weekend and for last six months. Starting the engine blew the fuse which is fitted in line on positive feed. Have replaced the battery with a new one and fuse and now electric working in the back. However, when I start the engine the control panel and electrics do not work although the fuse does not blow. Checked all fuses I can see are ok. Any ideas?