Your model number seems to be missing several digits at the end of it.
Sears/Kenmore model numbers are usually 3 digits, a period and then another eight digits.

Also I am not sure what you mean by "microwave fan"
Is this an above stove microwave that also includes an exhaust fan?

If it is then this is definitely a bad situation.
Microwaves pull a fair amount of current and although not part of most electrical codes it is advisable to have them on a separate line.
Also depending on the type of microwave they can cause spikes on the line as the magnetron turns on/off.

I do not know what type of mini line tester you are using but if it is one with just idiot lights then in my opinion it is pretty useless especially when working with a 240 volt circuit. Get yourself a proper multimeter and then check the power.

You can get a decent digital multimeter for under $20.00. You do not need fancy though it is nice if the leads are a couple feet long.
If it saves ordering one unnecessary part it has paid for itself and you end up owning a useful tool.
Most places will not let you return electrical parts so if you order it, you own it.
A couple things to watch when measuring ohms and continuity
1. Always remove power from the machine otherwise you could blow your meter.
2. Always disconnect at least one side of any device you are checking. This eliminates the possibility of measuring an alternate/parallel circuit path.
3. When checking for closed contacts and continuity use the lowest scale (Usually 200 ohms). Then try higher scales. This scale is 0 to 200 ohms so if the device you are measuring is 300 ohms this scale would show an open circuit which it is not, you are just measuring outside the scale's dynamic range.
4. When you start always short the meter leads together. This will tell you that the meter is working and if there is any 0 offset.

There is a good STICKY at the start of this forum about it's use.