Symptom Chart: Four-Wheel Drive Systems
WARNING: This page is about a different car, the 2015 Ford F-150. However, it is still accessible from the selected car via links, so may be relevant.
Diagnostics in this service information assume a certain skill level and knowledge of Ford-specific diagnostic practices. Refer to: Diagnostic Methods .
| Symptom | Possible Sources | Action |
|---|---|---|
| No communication with the TCCM | Scan tool DLC TCCM Wiring, terminals or connectors |
REFER to: COMMUNICATIONS NETWORK . |
| The 4X4 mode indicators do not operate correctly/do not operate | IPC 4WD system fault HS-CAN TCCM |
To diagnose the 4X4 mode indicators do not operate correctly/do not operate, Refer to: INSTRUMENTATION, MESSAGE CENTER AND WARNING CHIMES . |
| The vehicle does not shift between 2H (2WD) and 4X4 modes correctly | Wiring, terminals or connectors MSS Transfer case TCCM |
GO to Pinpoint Test L |
| The vehicle does not shift between 4A (4X4 AUTO) and 4H (4X4) modes correctly | Wiring, terminals or connectors IWE IWE solenoid Transfer case Vacuum leaks Front axle assembly TCCM MSS |
GO to Pinpoint Test D |
| Vehicle has no torque or inadequate torque at front wheels in 4A (4X4 AUTO) mode | Transfer case and related components IWE and related components Wheel/tire assemblies |
GO to Pinpoint Test J |
| The vehicle does not shift between 4H (4X4) and 4L (4X4 LOW) modes correctly | Wiring, terminals or connectors TR sensor ABS wheel speed inputs IWE TCCM Transmission drag torque |
GO to Pinpoint Test E |
| 4WD does not engage at speed correctly | Transfer case clutch Transfer case TCCM Front axle assembly Wiring, terminals or connectors |
GO to Pinpoint Test F |
| The front axle does not engage/disengage correctly | Wiring, terminals or connectors Fuses MSS IWE IWE solenoid Transfer case Vacuum leaks Front axle assembly TCCM |
GO to Pinpoint Test C |
| The 4WD system jumps out of gear | IWE vent line(s) Transfer case MSS |
GO to Pinpoint Test G |
| Unable to achieve flat tow (neutral tow) mode | Wiring, terminals or connectors HS-CAN IPC TCCM Door ajar switch Ignition switch |
REFER to: Neutral Flat Tow Activation and Deactivation . |
| Unable to duplicate customer concern | 4WD system and/or related components | GO to Pinpoint Test J |