Symptom Chart

Condition	Possible Sources	Action
No communication with the instrument cluster	Circuitry Instrument cluster	REFER to MODULE COMMUNICATIONS NETWORK .
No communication with the smart junction box (SJB)	Circuitry SJB	REFER to MODULE COMMUNICATIONS NETWORK .
The control illumination is inoperative	SJB	Go to Pinpoint Test A .
The instrument cluster illumination is inoperative	Instrument cluster	CHECK the audio unit illumination for correct operation. If the audio unit illumination operates correctly, INSTALL a new instrument cluster. REFER to INSTRUMENT CLUSTER . TEST the system for normal operation. If the audio unit does not operate correctly, REFER to MODULE COMMUNICATIONS NETWORK to continue diagnosis of the communications network.
The audio unit illumination is inoperative	Audio unit	CHECK the instrument cluster illumination for correct operation. If the instrument cluster illumination operates correctly, REMOVE the audio unit. REFER to INFORMATION AND ENTERTAINMENT SYSTEMS . SEND it to an authorized repair facility. TEST the system for normal operation after the repair. If the instrument cluster illumination does not operate correctly, REFER to MODULE COMMUNICATIONS NETWORK to continue diagnosis of the communications network.
The electronic automatic temperature control (EATC) illumination is inoperative	EATC module	CHECK the instrument cluster illumination for correct operation. If the instrument cluster illumination operates correctly, INSTALL a new EATC module. REFER to CLIMATE CONTROL SYSTEM - GENERAL INFORMATION AND DIAGNOSTICS . TEST the system for normal operation. If the instrument cluster illumination does not operate correctly, REFER to MODULE COMMUNICATIONS NETWORK to continue diagnosis of the communications network.
The window control switch illumination is inoperative	Circuitry Window control switch	For MKZ, go to Pinpoint Test C . For all others, 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 . TEST the system for normal operation. If the power windows do not operate correctly, REFER to GLASS, FRAMES AND MECHANISMS to continue diagnosis of the power windows.
The door lock control switch illumination is inoperative	Circuitry Door lock control switch	For MKZ, go to Pinpoint Test C . For all others, CHECK the operation of the door locks. If the door locks operate correctly, go to Pinpoint Test F . If the door locks do not operate correctly, REFER to HANDLES, LOCKS, LATCHES AND ENTRY SYSTEMS to continue diagnosis of the door locks.
The steering wheel control illumination is inoperative	Circuitry Steering wheel control switch(es) Clockspring	Go to Pinpoint Test B .
One or more module-controlled illumination source(s) is inoperative	Circuitry Illumination source(s) SJB	Go to Pinpoint Test C .
The control illumination is always on	Circuitry SJB	Go to Pinpoint Test D .
The control illumination does not dim	Circuitry Instrument panel dimmer switch (part of the headlamp switch assembly) SJB	Go to Pinpoint Test E .
A single illumination source is inoperative - non-dimmable illumination source	Circuitry Ashtray (MKZ) Roof opening panel switch Roof opening panel module Door lock control switch(es) (Fusion, Milan) SJB	Go to Pinpoint Test F .