Bought a engine scanner and it will not link to my 98 Lincoln Navigator wondering why and if it's compatable??

 

what "engine scanner" did you buy?

Some cheap OBD II Bluetooth scanners will not connect to the ECM. I got one off amazon for like $6 that will not work on my '02, but works on an '04.
I have a cheap plug in code reader that will work on any OBD II vehicle I have plugged it in to, but it is only a code reader, can not read any live data with it.

 

There is a dedicated fuse for the DTC connector. Check for a blown 5 amp fuse in the under dash fuse panel. (I don't remember the slot off the top of my head).