On Saturday I was climbing the Colle della Fauniera (Colle dei Morti) and about halfway up my Shimano Flight Deck (SC-6501) and the trip distance, trip time, average speed and pace arrows stopped working. The only thing that continued to function were the KMH and RPM.
When I arrived home, I started to see if the other functions would work and when pressing in the mode button (RH button), I could not select any oother function. The clock would come up and then the gearing selection and that is all.
I have only had the unti since July and have already replaced the wirelsss sensor battery so maybe the head unti battery requires replacement as well?
I reset the computer and started from scratch and the unti still does not work properly.
When it comes to troubleshooting electronics, do it in stages, simplest, most obvious first. I'd replace the battery, then if that doesn't work, put some contact cleaner on the brifter switch(es). You might also check the pin contacts on the housing/bracket. I have a Flight Deck on my tandem and sure like (most of) the features. I have heard that sometimes the switches need some attention, however, mine works fine, but it's only 3 months old with only about 1,000 miles on it. Let us know what you discover... Good luck, OHB
I had the exact same issues earlier in the year. After working flawlessly, my FlightDeck started getting "flakey." Replaced all the batteries, etc.
Turned out to be be the shifter contacts. According to a local mechanic, they can be a little fussy in terms of alignment. My suggestion would be to pull them off, make sure they're clean and reassemble.