Symptom Chart

Condition	Possible Sources	Action
No communication with the smart junction box (SJB)	Fuse Circuitry SJB	REFER to MODULE COMMUNICATIONS NETWORK article.
The control illumination is inoperative - all hardwired illumination	Fuse Circuitry Auxiliary climate control assembly SJB	Go to Pinpoint Test A .
The control illumination is always on - all hardwired illumination	Circuitry SJB	Go to Pinpoint Test B .
All instrument panel illumination does not dim	Circuitry Instrument panel dimmer switch SJB	Go to Pinpoint Test C .
The window control switch illumination is inoperative - Expedition only	Window control switch	CHECK the operation of the power windows. If the power windows operate correctly, INSTALL a new window control switch. REFER to GLASS, FRAMES AND MECHANISMS article. TEST the system for normal operation. If the power windows do not operate correctly, REFER to GLASS, FRAMES AND MECHANISMS article.
The steering wheel control illumination is inoperative	Circuitry Steering wheel control switch(es) Steering wheel control switch harness Clockspring	Go to Pinpoint Test D .
The instrument cluster illumination is inoperative	Instrument cluster	INSTALL a new instrument cluster. REFER to INSTRUMENT CLUSTER article. TEST the system for normal operation.
The audio unit illumination is inoperative	Audio unit	REMOVE the audio unit. REFER to INFORMATION AND ENTERTAINMENT SYSTEMS article. SEND it to an authorized repair facility. TEST the system for normal operation after the repair.
The climate control module illumination is inoperative	Climate control module	INSTALL a new climate control module unit. REFER to CLIMATE CONTROL article. TEST the system for normal operation.
The digital versatile disc (DVD) player illumination is inoperative	DVD player	REMOVE the DVD player. REFER to INFORMATION AND ENTERTAINMENT SYSTEMS article. SEND it to an authorized repair facility. TEST the system for normal operation after the repair.
The individual component illumination is inoperative	Circuitry Adjustable pedal switch Ash receptacle (Navigator only) Auxiliary climate control assembly (Expedition only) Clock (Navigator only) Floor Shifter Four wheel drive (4WD) switch Hazard flasher switch Headlamp switch Illumination source Overhead console Message center switch Door lock control switch Power window control switch (Navigator only)	Go to Pinpoint Test E .