夏普打印机AR-256L错误代码U2-40指示灯全灭 ,U2-40 CRUM communication error CRUM通讯错误 U2-40 error try pulling out the toner cartridge an d firmly reinstalling it. If that doesn't work you must install a new toner cartridge. There is a CRUM chip on the cartridge that keeps up with how many impressions have been made with that cardridge. You cannot "refill" these cartridges without replacing the CRUM. This problem occurs frequently with remanufactured cartridges. 苏州夏普报修电话696l6769,维修,售后服务