So a follow up...
I went to my Ford dealer today and inquired about the door latch issue. They of course do admit its a problem, and that the first step they can take is some sort of electrical contact cleaning process that takes about 20 minuets. BUT... they admit this may or may not solve the issue, and it would be better to just replace the latch.
I used the information from you all here on the forum to ask some more questions of their mechanic, not the service department rep.
The mechanic admitted that the original latches and sensors are not a 'sealed" unit, so dirt, debris, and corrosion get into the latch and degrade the sensor contact to the point that it no longer functions...this is why they recommend replacement as opposed to cleaning the contacts. This corrosion also seems to occur mostly (but not always) on the door most used by the customer (ie, drivers door), since its opened the most and exposed to the elements most often.
I then asked if the new latch, (having read on here that the part number has changed, indicating some change in the part), was a "sealed" unit, to prevent further corrosion. He said it is NOT, it's simply a different sensor, and possibly more robust than the one originally installed on the car.
They cannot however, guarantee that this one will not fail after extended use as he has had to replace multiple door latches on some Fleet Edges and Explorers that he's already replaced before.
In short, even with a replaced latch, it may fail further down the line due to its "unsealed' design as he put it. The best advice the dealer mechanic could offer, from what he has seen, is to keep the latch clean and lubricated...and basically try not to leave your door open in the rain...and after car washes, open the door and dry out the door frame and where the latch secures to the frame of the car to prevent moisture from getting in.
Edited by rldechant, 14 March 2017 - 02:55 PM.