“A suspected computer malfunction aboard the ferry Cathlamet put the boat out of service until further notice Tuesday, forcing Washington State Ferries to bring in a replacement boat that afternoon.The problem started Tuesday morning, was temporarily fixed, then reoccurred shortly after noon, forcing ferry personnel to take the Cathlamet out of service. The trouble began seconds after a car filled the last available space aboard the ferry for the 9:30 a.m. run when the Cathlamet started pulling away from the dock on its own. Dan Ferguson, the Clinton dock supervisor, said Tuesday afternoon that he had not yet received word about exactly why this happened.The boat’s captain brought the Cathlamet back to the dock, checked to make certain the malfunction would not happen unexpectedly again, then the ferry boat and dock personnel began backing cars off the boat.It was a nicely coordinated exit, said Steve White, who had returned to the ferry line to await the next boat. The crew told us it was a mechanical breakdown and kept us informed the whole time, said Libby McCauley of Greenbank. Everyone was very polite. A few drivers began honking their horns, but some people went over to talk to them, and that stopped.McCauley and White agreed that the mood was one of resigned acceptance of what White called business as usual. McCauley and others lent their cell phones to those without them so they could make calls to people waiting for them. Ferry personnel offered refunds to those who didn’t wish to wait. Toll collector Don Anderson explained the situation to ferry patrons and said most of them were just fine with it.And those waiting to get off the Cathlamet were entertained, McCauley said, by the sight of a gray whale that gave us a show. Because the dock is still in the midst of reconstruction, there is only one slip available for ferryboats. This made it impossible to load the cars onto the ferry Kittitas while the Cathlamet was in dock. Ferguson said it took ferry personnel until just after 10:30 a.m. to find the problem and fix the malfunctioning Cathlamet. An 11 a.m. run left on time.State Ferries brought the 70-car ferry Quinault onto the run by rush hour Tuesday. That ferry carries about 50 fewer cars than the Cathlamet. The Cathlamet has been one of the most dependable boats in the fleet, and recently completed its second year without missing a run.”