Hello Fatbelly, thank you for posting the pictures. I can see clearly now where the problem was. I take Greywolf's point that situation may have been due to a marginal connection causing heat damage. When I inspected my wiring loom this evening it was rock solid and very difficult to move away from the frame cross member it was resting on. I looked closely at the tape binding the loom and there may have been the early stages of wear but it was difficult to tell, and the bike is still low mileage. However, because I am risk averse I decided to do some remedial work. Too late for you I know but others may want to consider this.
1st Pic, I got hold of a soft rubber bicycle handlebar grip and split it down the middle with a craft knife.
2nd Pic, I removed the two bolts and two pop-out panel connectors from the black side panel and prised it away from the bike.
3rd Pic, I fed the flattened handlebar grip from underneath the bike pushing it forward up and over the offending cross member and underneath the wiring loom. I then cable tied it at the forward position, in front of the fuel tank rear support.
4th Pic, working under the bike again I cable tied the rear of the handlebar grip making sure I didn't tie anything else to the loom.
5th Pic, I trimmed the cable ties and put the side cover fastenings back. This is what the installation looks like from underneath when all is back together again.
If I get a problem now at least I should have eliminated the loom being chafed by the frame.