Sounds like it is most likely in the cigarette lighter circuitry. If need be, disconnect the lighter completely and then try it. If it doesnt blow after awhile then you know you need to replace that. If it still blows, then it is time to get yourself a wiring diagram and start troubleshooting via process of elimination. Just follow the diagram and disconnect the different components until you no longer blow the fuse. Then you know where your problem is. It would be wise to get yourself a few spare fuses for your troubleshooting.

Good luck,

__________________
Frank
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