Having done some reasonable surfing round on these pages and finding ECU fuse blowing topics, it seems that although the symptom is the same, the cause may well not be in this case.
I recently had a Battery master switch fitted, which has been very useful as my garage has no power. When I came to the car on Wednesday night, and enabled the switch, I then had no fuel pump etc - traced to a blown ECU fuse. Duly replaced, all seemed well. The following morning, same drill, same result: blown ECU fuse. Everything seems to be running fine once the fuse is replaced. I tried swapping the fuse for a 30A this afternoon, but that blows in exactly the same way. Clearly something not right.
Is this likely to be an earthing issue, and if so, where should I start to look? I took the knee panel off this afternoon to check the connections on the BMS, which all look fine, except that the earth to the chassis looks a bit corroded (slight concern since switch was only fitted 2 1/2 months ago). I'll clean this up tomorrow. Is this 'channel' behind the knee panel a known water trap? Given that there seems to be a gap in the panels straight out to the edge of the bonnet, I might fill this up, though not sure what with.
Any pointers from you experienced electronics gurus would be much appreciated.
Many thanks
Paul