Is he getting any info from the GPS unit (wrong year/date). May be the roll over bug. If dead, the LX200 GPS is the same. The wires from the GPS to the left fork arm board are a known problem to check. Try unplugging the connectors a few times also to clean the connections.
Rollover bug was the first thing I thought of, too. In what way did it "stop working"?
My advice would be to just turn GPS off. He will have to enter the time and date each time the scope is started, but unless there is a compelling need to have the time within a gnat's eyelash - which never or almost never happens - within a couple of minutes or so is plenty good. It remembers the previous location, or he can select from several custom locations if he uses it at the same places frequently. Specifying the location within 100 km or so should almost always be fine as well.
Our local club has an RCX 400 in a metal dome, and when the GPS was working (before the rollover) it always took a long time for it to get a fix once the slit was opened. This usually meant it took longer than half an hour after opening the dome to get the telescope up and running since it refused to proceed until it got a GPS fix. The easy solution was to turn the GPS off and enter the time and date by hand, which frequently saved 15 minutes or so. We turned it back on late last spring to see if it was affected by the rollover, and, yup... the date was about 80 years off. It has been turned off ever since.