Look for in-line fuse holders or secondary breakers near the batteries that provide constant power to the ECM or transmission controllers.
Most FL-series trucks from this era house the main fuse and relay panel behind a plastic cover in the lower center dash area, below the radio or cup holders. 1994 freightliner fl80 fuse box diagram
Business Class Driver's Manual - Collage (1-9) - Freightliner Look for in-line fuse holders or secondary breakers
on the passenger side or in the center beneath the cup holder area. You may need to remove a bottom panel to access it. Engine Compartment 1994 freightliner fl80 fuse box diagram
Freightliner FL80 Fuse Box Diagrams & Locations - JustAnswer
Since diagrams for 1994 models aren't always readily available online, here is how to identify circuits: The Cover is Key