Four-Wheel Drive Systems (ESOF) - Excursion & F250-F550 Super Duty

• Application
• Description
• Operation
  • Electronic Shift System
  • Module Location
  • Input Devices
    • Brake On/Off Switch
    • Clutch Pedal Position Switch
    • 4WD Mode Switch
    • Transmission Range Sensor
    • Vehicle Speed Sensor
  • Output Devices
    • Transfer Case Shift Motor
    • Pulse Vacuum Hublock Vacuum Solenoid
• Trouble Shooting
  • Preliminary Inspection
  • Symptom Diagnosis
    • Vehicle Does Not Shift Between 2WD & 4WD Modes Properly
    • Vehicle Does Not Shift Between 4WD High To 4WD Low Properly
    • Front Axle Not Engaging (T/C Motor Movement & Front Drive Axle Okay)
    • 4X4 Indicator Light Always On
    • Low Range Indicator Always On
    • No Communication With GEM
• Diagnosis & Testing
  • Equipment Hook-Up
  • Retrieving Diagnostic Trouble Codes
  • Diagnostic Trouble Code Definitions
  • Electronic Shift Functional Test
  • Gem On-Demand Self-Test
  • Clearing Diagnostic Trouble Codes
  • Retrieving Parameter Identification Information
• Diagnostic Tests
  • Test A: Vehicle Does Not Shift Between 2WD & 4WD Modes Properly
  • Test B: Vehicle Does Not Shift Between 4WD High & 4WD Low Properly
  • Test C: Front Axle Not Engaging Properly
  • Test D: 4X4 High Indicator Always On, 4WD System Okay
  • Test E: Low Range Indicator Always On
  • Test F: No Communication With Gem Module
• Removal & Installation
  • Mode Select Switch (MSS)
    • Removal & Installation
  • HUBLOCK
    • Removal & Installation
  • Pulse Vacuum HUBLOCK (PVH) Solenoid
    • Removal & Installation
  • HUBLOCK Vacuum Reservoir
    • Removal & Installation
  • GEARMOTOR Encoder Assembly
    • Removal & Installation
  • Mode Indication Switch
    • Removal & Installation
• Wiring Diagrams