Check the 4 pin plug connection is good and not burnt out. The pins have been known to push back and have a high resistance that leads to heat and the plug melting. If the plug and/or socket has melted then the part numbers are in the alternative parts list here:

https://www.dropbox.com/s/cvo7sehb6o4q9la/Updated%20List%2011%20June%202019.pdf?dl=0

Top of Page 6.

Check the earth connection. The HD rectifier (74540-01) seems to be far more reliable than the standard CE 601 unit.

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