Symptom Chart - Four-Wheel Drive Systems
WARNING: This page is about a different car, the 2018 Lincoln MKC. 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 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.
| Condition | Possible Sources | Actions |
|---|---|---|
| Unable to duplicate customer concern; no Diagnostic Trouble Codes (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 | Transfer case overheating | INSPECT the duct that cools the transfer case sump is free and clear of debris. Clear as necessary. |
| Fuse(s) Wiring, terminals or connectors Active Torque Coupling (ATC) solenoid AWD Relay Module PCM Active Torque Coupling Clutch |
GO to Pinpoint Test D | |
| Wheels/tires | REFER to: Wheels and Tires . | |
| Transfer case | REFER to: Transfer Case . | |
| Rear Drive Unit (RDU) | REFER to: Axle Assembly . | |
| Vehicle binds in a turn or resists turning/pulsates or shudders in a straight line | Wheels/tires | REFER to: Wheels and Tires . |
| Transfer case | REFER to: Transfer Case . | |
| Driveshaft | REFER to: Driveshaft . | |
| Wiring, terminals or connectors Active Torque Coupling (ATC) solenoid Active Torque Coupling Clutch AWD Relay Module |
GO to Pinpoint Test E | |
| Brake system | REFER to: Brake System . | |
| Wheel bearings | REFER to: Suspension System . | |
| Halfshafts | REFER to: Front Drive Halfshafts . | |
| ABS | REFER to: Anti-Lock Brake System (ABS) And Stability Control . | |
| Tire/axle out of acceptable range | Wheels/tires ABS |
GO to Pinpoint Test B |