I am sure there is battery disconnect, reconnect procedures on this site,, but I found a good procedure I use on "Howard's Volvo" site.

I had the exact same symptoms and after researching a new dealer module at $538 or a lifetime warranty module from Erie Vovo for $150. I went with Erie Vovo. The first unit they sent did not work, but the quickly sent 2 more modules to try, the second one I put in works fine. They sent a return labe...