F 150 Heritage 4WD Pickup V8-5.4L SOHC VIN Z Bi-fuel (2004)
Four Wheel Drive Selector Switch: Description and Operation
4X4 MODE SWITCH
Typical 4X4 Switch
The generic electronic module (GEM) or the 4x4 module (4x4M) provides the PCM with an indication of 4x4L. This input is used to adjust the shift
schedule. A 5.0 volt module pull-up indicates 4x4H or 2WD (Figure 53).