Symptom Chart

WARNING: This page is about a different car, the 2013 Ford Mustang. However, it is still accessible from the selected car via links, so may be relevant.

SYMPTOM CHART

Condition	Possible Sources	Action
All dimmable illumination is inoperative	Wiring, terminals or connectors Instrument panel dimmer switch Smart Junction Box (SJB)	GO to PINPOINT TEST A .
All dimmable illumination does not dim	Wiring, terminals or connectors Instrument panel dimmer switch SJB	GO to PINPOINT TEST B .
All dimmable switch illumination is inoperative	Fuse Wiring, terminals or connectors SJB	GO to PINPOINT TEST C .
All dimmable switch illumination is always on	Wiring, terminals or connectors SJB	GO to PINPOINT TEST D .
The steering wheel switch illumination is inoperative	Wiring, terminals or connectors Steering wheel switch Steering wheel harness Clockspring	GO to PINPOINT TEST E .
One or more switch illumination is inoperative	Wiring, terminals or connectors Convertible top switch Headlamp switch Hazard flasher lamp switch Floor shifter (automatic transmission) Door lock control switch Window control switch	GO to PINPOINT TEST F .
All network controlled illumination is inoperative/does not dim	Medium Speed Controller Area Network (MS-CAN) SJB	CARRY OUT the network test. If the scan tool responds with no communication to the SJB, REFER to MODULE COMMUNICATIONS NETWORK . If the scan tool communicates with the SJB, INSTALL a new SJB. REFER to MULTIFUNCTION ELECTRONIC MODULES . TEST the system for normal operation.
The Instrument Panel Cluster (IPC) illumination is inoperative/does not dim	MS-CAN IPC	CARRY OUT the network test. If the scan tool responds with no communication with the IPC, REFER to MODULE COMMUNICATIONS NETWORK . If the scan tool communicates with the IPC, INSTALL a new IPC. REFER to INSTRUMENTATION, MESSAGE CENTER, AND WARNING CHIMES . TEST the system for normal operation.
The Front Controls Interface Module (FCIM) illumination is inoperative/does not dim	FCIM MS-CAN	CARRY OUT the network test. If the scan tool responds with no communication with the FCIM, REFER to MODULE COMMUNICATIONS NETWORK . If the scan tool communicates with the FCIM, INSTALL a new FCIM. REFER to INFORMATION AND ENTERTAINMENT SYSTEMS . TEST the system for normal operation.
The Front Display Interface Module (FDIM) illumination is inoperative/does not dim (vehicles without navigation)	MS-CAN FDIM	CARRY OUT the network test. If the scan tool responds with no communication with the FDIM, REFER to MODULE COMMUNICATIONS NETWORK . If the scan tool communicates with the FDIM, INSTALL a new FDIM. REFER to INFORMATION AND ENTERTAINMENT SYSTEMS . TEST the system for normal operation.
The Front Display Interface Module (FDIM) illumination is inoperative/does not dim (vehicles with navigation)	FDIM MS-CAN	REFER to INFORMATION AND ENTERTAINMENT SYSTEMS .