Pinpoint Test B : The LINCOLN Grille Emblem Lamp Is Inoperative Or Always On

WARNING: This page is about a different car, the 2018 Lincoln Navigator. However, it is still accessible from the selected car via links, so may be relevant.

B1 CHECK FOR HCM (HEADLAMP CONTROL MODULE) DIAGNOSTIC TROUBLE CODE (DTCS)
- Ignition ON.
- Using a diagnostic scan tool, perform the HCM self-test.
Are any HCM Diagnostic Trouble Code (DTCs) present?

Yes DIAGNOSE the HCM Diagnostic Trouble Code (DTCs) first. REFER to: Headlamps .

No GO to B2

B2 CHECK FOR SUPPLY VOLTAGE TO THE GRILL EMBLEM LAMP

Ignition OFF.

Disconnect: Signature Lamp (grill emblem) C1796 .

Ignition ON.

Measure:

Positive Lead	Measurement / Action	Negative Lead
C1796-1	Courtesy of FORD MOTOR COMPANY	Ground

Is the voltage greater than 11 volts?

Yes

GO to B4

No	VERIFY BJB fuse 60 (5A) is OK. If OK, GO to B3 If not OK, Refer to the Wiring Diagram Information to identify the possible causes of the circuit short.

B3 CHECK GRILL EMBLEM LAMP VOLTAGE SUPPLY CIRCUIT FOR AN OPEN

Ignition OFF.

Disconnect: BJB C1035D .

Measure:

Positive Lead	Measurement / Action	Negative Lead
C1796-1	Courtesy of FORD MOTOR COMPANY	C1035D-10

Is the resistance less than 3 ohms?

Yes	INSTALL a new BJB.

No	REPAIR the circuit.

B4 CHECK THE GRILL EMBLEM LAMP GROUND CIRCUIT FOR AN OPEN

Measure:

Positive Lead	Measurement / Action	Negative Lead
C1796-1	Courtesy of FORD MOTOR COMPANY	C1796-2

Is the voltage greater than 11 volts?

Yes

GO to B5

No	REPAIR the circuit.

B5 CHECK FOR SIGNAL VOLTAGE TO THE GRILL EMBLEM LAMP

Place the headlamp switch in the PARKLAMPS position.

Measure:

Positive Lead	Measurement / Action	Negative Lead
C1796-3	Courtesy of FORD MOTOR COMPANY	Ground

Is the voltage greater than 11 volts?

Yes	INSTALL a new grill emblem.

GO to B6

B6 CHECK GRILL EMBLEM LAMP SIGNAL CIRCUIT FOR A SHORT TO GROUND

Ignition OFF.

Disconnect: LH Headlamp C1758 .

Measure:

Positive Lead	Measurement / Action	Negative Lead
C1796-3	Courtesy of FORD MOTOR COMPANY	Ground

Is the resistance greater than 10, 000 ohms?

Yes

GO to B7

No	REPAIR the circuit.

B7 CHECK GRILL EMBLEM LAMP SIGNAL CIRCUIT FOR AN OPEN

Measure:

Positive Lead	Measurement / Action	Negative Lead
C1796-3	Courtesy of FORD MOTOR COMPANY	C1758-9

Is the resistance less than 3 ohms?

Yes

CHECK the internal headlamp harness for open or shorted circuits and damaged or pushed-out pins. If the harness is OK, INSTALL a new adaptive front lighting module. REFER to: Adaptive Front Lighting Module . If the harness is not OK, REPAIR the harness. If the harness cannot be repaired, INSTALL a new headlamp assembly. REFER to: Headlamp Assembly .

No	REPAIR the circuit.