You have a short, if it does it when you plug the unit to power(not turned on and working) problem is where the wall voltage (AC voltage ) comes in and I would in that case look for the large AC filter cap to be buldged or out of its normal shape(photo attached of a typical one).
If it does blow the fuse when turned on to cook suspect the Diode that most use, the Magnetron that does the cooking or the inverter board that powers the Magnetron.
See attached photos of typical ones, some people can or cannot do this kind of repair but this will give you some possible reasons--when a fuse blows there is a short.
Typical diode(should not read short across it.
Typical Magnetron, cannot be tested easily but would have to be replaced to know--the units vary in shape very little..
kenmore brewnwave blows fuse - 12_19_2012_2_48_53_pm.jpgages/12_19_2012_2_48_53_pm.jpg" alt="12_19_2012_2_48_53_pm.jpg" />Typical AC cap, these will vary in shape as some are more oval but the outer part is metal coated with clear plastic. This can be tested with a ohm meter.
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You have a short, if it does it when you plug the unit to power(not turned on and working) problem is where the wall voltage (AC voltage ) comes in and I would in that case look for the large AC filter cap to be buldged or out of its normal shape(photo attached of a typical one).
If it does blow the fuse when turned on to cook suspect the Diode that most use, the Magnetron that does the cooking or the inverter board that powers the Magnetron.
See attached photos of typical ones, some people can or cannot do this kind of repair but this will give you some possible reasons--when a fuse blows there is a short.
Typical diode(should not read short across it.
Typical Magnetron, cannot be tested easily but would have to be replaced to know--the units vary in shape very little..
kenmore brewnwave blows fuse - 12_19_2012_2_48_53_pm.jpgages/12_19_2012_2_48_53_pm.jpg" alt="12_19_2012_2_48_53_pm.jpg" />Typical AC cap, these will vary in shape as some are more oval but the outer part is metal coated with clear plastic. This can be tested with a ohm meter.