Problems With G.E.'s WattStation Charger for Some Nissan Leafs After reports that its WattStation home charger had damaged the on-board charging system of some Nissan Leaf electric cars, G.E. Energy issued a statement Friday conceding that some Leaf owners had encountered problems and that the company was "actively working with Nissan to help determine the source of this issue." The G.E. subsidiary said it had not encountered similar issues with other electric car models. The WattStation, designed by Yves Behar to be more attractive and easier to use than previous chargers, was initially shown by the company in 2010. The first home units were sold in July 2011. A representative of a Nissan dealership in the San Francisco Bay Area sent an e-mail to Leaf customers on Thursday, warning them to stop using the charger. In the message, Rafael Carballo, the E.V. sales leader at Hanlees Hilltop Nissan in San Pablo, Calif., said Nissan had "documented" cases of the G.E. station's damaging Leaf charging systems. "It is recommended that you don't use G.E. charging stations at this time," he wrote. The dealership's warning was first reported by PlugInCars.com. In a telephone interview, Mr. Carballo said his e-mail was based on information sent to him by a Nissan regional operations manager. "We thought it would be good to alert our customers," he said. Mr. Carballo said he was not aware of WattStation problems affecting cars sold by his own dealership. A spokeswoman for Nissan North America, Katherine Zachary, said in an e-mail, "There's no official Nissan policy instructing customers not to use G.E. WattStations." Sean Gannon, a spokesman for G.E. Energy, said in the company's statement, "Since its launch in 2011, G.E."s WattStation has performed as designed, thousands of units have been shipped and it has received positive reviews from E.V. drivers." The statement said the charging issue had been "raised by 11 Nissan Leaf owners." Some users of the owners" forum at MyNissanLeaf.com have posted accounts of their problems with the WattStation charger. "Benjenn," described as a Leaf owner in Edmond, Okla., wrote in June that after he used the home-based WattStation six or seven times, he plugged it in again and "everything went off." The local Nissan dealer reported that the car's on-board charging unit had malfunctioned, Benjenn said, and that problems had previously arisen with G.E. chargers. Other forum users, however, described their WattStations as working flawlessly.