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Symptom Chart

WARNING: This page is about a different car, the 2018 Ford Edge. However, it is still accessible from the selected car via links, so may be relevant.

Diagnostics in this article assume a certain skill level and knowledge of Ford-specific diagnostic practices. REFER to: Diagnostic Methods .

In most circumstances, the PCM sets DTCs to help guide with diagnostics. Refer to the DTC Chart: AWD System - PCM  before using the symptom chart. The Symptom column lists the vehicle condition. The Possible Sources column lists a detailed vehicle condition. The Action column lists the action to be performed to determine the cause of the condition. Each action lists the components that can cause the system and the individual components in that system. The components are listed in order of disassembly. Use the list of components and the required action to focus on disassembly inspections for the root cause of the concern.

Symptom Chart - Four-Wheel Drive Systems 

Condition Possible Sources Actions
Unable to duplicate customer concern; no DTC present The concern description is inaccurate CARRY OUT the AWD System Functional Test. GO to Pinpoint Test A 
Vehicle has no or inadequate torque at rear wheels Fuse
Wiring, terminals or connectors
Active Torque Coupling (ATC) solenoid
Active Torque Coupling (ATC) Clutch
AWD Relay Module
PCM
GO to Pinpoint Test C 
Wheels/tires Check wheels and tires for damage. REFER to: Wheels and Tires .
Rear axle Check rear axle for damage. REFER to: Rear Drive Axle and Differential .
PTU mechanical failure Check PTU for damage. REFER to: Transfer Case 2.0L EcoBoost . REFER to: Transfer Case 2.7L EcoBoost . REFER to: Transfer Case 3.5L Duratec .
Vehicle binds in a turn or resists turning/pulsates or shudders in a straight line Wheels/tires Check wheels and tires for damage. REFER to: Wheels and Tires .
Wiring, terminals or connectors GO to Pinpoint Test E 
Driveshaft Check driveshaft for damage. REFER to: Driveshaft .
Wiring, terminals or connectors
Active Torque Coupling (ATC) solenoid
Active Torque Coupling (ATC) Clutch
AWD Relay Module
GO to Pinpoint Test E 
PTU mechanical failure Check PTU for damage. REFER to: Transfer Case 2.0L EcoBoost . REFER to: Transfer Case 2.7L EcoBoost . REFER to: Transfer Case 3.5L Duratec .
Driveshaft Check driveshaft for damage. REFER to: Suspension System .
Wheel bearings Check wheel bearings for damage. REFER to: Suspension System .
ABS CHECK the ABS. REFER to: Anti-Lock Brake System (ABS) and Stability Control .
Halfshafts Check the halfshafts for damage. REFER to: Rear Drive Halfshafts .
Tire/axle out of acceptable range Wheels/tires
ABS
GO to Pinpoint Test B