Symptom Chart

Diagnostics in this service information assume a certain skill level and knowledge of Ford-specific diagnostic practices. Refer to Diagnostic Methods in Service Information for information about these practices.

In most circumstances, the PCM sets DTCs to help guide with diagnostics. Refer to the DTC Chart before using the symptom chart. The Condition column lists the vehicle condition. The Source 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 caused 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

Condition	Possible Sources	Action
Unable to duplicate customer concern; no DTCs 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(s) Wiring, terminals or connectors ATC solenoid AWD relay PCM	GO to Pinpoint Test A .
	Wheels/tires	REFER to Wheels and Tires .
	PTU mechanical failure	REFER to Transfer Case - Power Transfer Unit (PTU) .
	Rear axle	REFER to Rear Drive Axle Differential .
Vehicle binds in a turn or resists turning/pulsates or shudders in a straight line	Wheels/tires	REFER to Wheels and Tires .
	PTU mechanical failure	REFER to Transfer Case - Power Transfer Unit (PTU) .
	Driveshaft	REFER to Driveshaft .
	Wiring, terminals or connectors ATC solenoid AWD relay PCM	GO to Pinpoint Test F .
	Brake system	REFER to Brake System - General Information .
	Wheel bearings	REFER to REFER to Suspension System - General Information .
	Halfshafts	REFER to Driveline System - General Information .
	ABS system	REFER to Anti-Lock Brake System (ABS) and Stability Control .
Tire/axle out of acceptable range	Wheels/tires ABS system	GO to Pinpoint Test C .