Bandit’s speedo goes blank

Q. I have a Suzuki Bandit 1250SA which is just coming up for three years old. It has developed an intermittent problem in that the speedo can go blank, though it is still backlit, and the rev counter will jam in red or return to zero and act up.

I thought it could be dampness somewhere in electrics and have dried them out several times but it can now happen in dry warm weather. The dealer advises that the system is not registering any problem.
Anon
 
A. The problem will be water in the number two wiring harness that is inside the fairing, interrupting the permanent live feed to the speedo and rev-counter. The speedo light stays on as it takes its feed from the headlight.

The reason the dealer’s diagnostic kit isn’t showing a fault is that it only checks the fuel injection.