When CBS sold Fender to its current owners in 1984 there was a transitional period from 1984 to 1987 with limited Fender USA production resulting in mostly Fender Japan and leftover stock being sold.
There are also Fender Contemporary Telecaster models with HSS or HH pickup configurations and switches for selecting pickup options.
They were designed to help identify the approximate manufacturing date of the guitar.
The pickups used in the Contemporary models were manufactured by Fujigen.
The early series are the most popular for collectors.
Also, some The Japanese serial number can be confusing too.
and both were being made at the same time from 1994 till 1997.
This means that the the serial numbers starting in 1994 ran consecutively on both the MIJ and the CIJ models while the MIJ logo was being phased out.