After about 4 months I finally found my hrm-dual, I changed the battery, but when I put it on it shows --.
I wet the diodes as always, I changed the polarity according to the instructions on this forum, nothing works. It connects to the watch (FR255) but doesn't detect my heart rate then disconnects.
It worked fine before I lost it.
Does anyone have any ideas what the problem could be? Thanks in advance.
