Went to plug in the block heater cord on my recently purchased D250 and saw sparks from the cord and the lights in my garage dimmed. After unplugging it I inspected the cord to see that there was a break in the cord with a piece of wire showing where cord goes into the plug end. I'm not an electrician so I dont know if this can be stripped back and a new end plug wired up or do I have to get a new cord altogether? If new cord where and how much? Thanks Bill