More than likely the heater core, located on the firewall on the passenger side under the hood, is shot or the hoses connecting the the heater core to the system are shot.
passenger side , front cylinder is # 1
At the front of the engine compartment on the passenger side
On a 1997 Lincoln Continental : If you mean air bags for the driver and front passenger ( YES )
The front relay is on the passenger side kind of hidden but you'll find it on the upper front right side on the passenger side.
It is in the right front corner of the engine compartment (passenger side)
They are the two interior trim panels just in front of the front doors in the driver and front passenger footwells
The general location is on the passenger side between the front tire and front bumper.
On a 2004 Lincoln Navigator : NO , the passenger compartment fuse panel / Power Distribution Box is combined in the front passenger footwell , behind the kick panel
Firing order on Lincoln ls 3.9 V8 driver side front to back 5678 passenger side front to back 1234
In the front passenger footwell by the kick panel
passenger side is 1234 front to back drivers side is 5678 front to back
On a 2004 Lincoln Navigator : ( NO , the passenger compartment fuse panel and the power distribution box are combined behind the kick panel in the front passenger footwell )