the wires and connectors seemed fine. they didn't look scorched at all, and there was no melted insulation.

The driver's side fan spins freely.

The passenger side fan does not. It's catching on something, either a blade catching on the shroud or broken motor parts.

Is a fan replacement something I can do myself in my apartment parking lot with simple tools?

(full socket set, metric wrenches, screwdrivers of varying sizes, pliers)

They are a little tricky, but I think you can do it.

Do a search on this site and you will find some tutorials from DIYer guys who have done it ..

Probably dark there , so you may want to take a closer look in the daylight..may just be a branch or road debries caught in between the fan blades and the condenser..

Anyway, that would cause both the fuse to blow and the lack of aux fan in traffic would cause your overheat condtion.
That blue sensor I had you unplug is calibrated to kick the high fans on at 105C, so if it does not, then the temp justs runs right up there ..[ as you know]..
The reason for unplugging the sensor for the test is b/c Benz designed a Default Fan Activation into the Control Unit so that if a sensor did crap out , the fans would automatically come on just to protect the engine in case a overheat condition presented itself with a broken/open sensor or wiring...
So, knowing that , we just use the 'Unplug " as a quicky test to verify aux fan circuit integrity...nice to know and a simple test that turns the fans on right off the bat....that's how we tracked it down to the relay fuse so fast..
Check it out and let me know how you make out.......hopefully you did no damage...................may even want to go for a new thermstat after all the over heating, but you will know more after getting the fans working...that is your first priority and the most likely diagnosis...........................

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A Dalton

Thank you very much for all your help.

I'll scrounge the money for a new fan, and buy a new cap and flush the coolant. If it's hot in the engine bay, will the visco clutch break?

Just an FYI...I have gotten some fans started up again on Mercedes. Other makes seem to be poorly made and don't take kindly to the following....

...anyways, whack the fan boss with a rubber mallet or similar and try it again....preferably while the fan is supposed to be running.

Have found the brushes stick in the holders and this frees them up if this is the problem.

Over to you again Arthur.........

.

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