Symptom Chart

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 .

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.

Four-Wheel Drive (4WD) System

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	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 A
The vehicle does not shift between 4H and 4L modes correctly	Wiring, terminals or connectors IWEs IWE solenoid Transfer case Vacuum leaks Front axle assembly TCCM MSS	GO to Pinpoint Test B
The 4WD does not engage at speed correctly	Transfer case and related components IWEs and related components Wheel/tire assemblies	GO to Pinpoint Test F
The transfer case jumps out of gear	IWE vent lines MSS Transfer case	GO to Pinpoint Test D
Unable to duplicate customer concern	4WD system and/or related components	GO to Pinpoint Test H
Rear wheels binding when turning corners with the ELD MSS set to OFF	Wiring, terminals or connectors Fuses MSS IWEs IWE solenoid Transfer case Vacuum leaks Front axle assembly TCCM	REFER to: Electronic Locking Differential (ELD) - Vehicles With: Ford 8.8 Inch Ring Gear. Refer to: Rear Drive Axle and Differential - Vehicles With: Ford 9.75 Inch Ring Gear.
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 .