PINPOINT TEST C : An Individual Or Group Of Flashing LEDs Is Inoperative Or Always On

C1 CHECK THE FLASHING LIGHT-EMITTING DIODES (LEDs)

Is only an individual flashing LED inoperative?

Yes	For a front park or turn or warn LED concern, GO to Pinpoint Test E . For all others, GO to C2.
No	GO to C4.

C2 CHECK FOR VOLTAGE TO THE FLASHING LIGHT-EMITTING DIODE (LED)

Measure:

Positive Lead	Measurement / Action	Negative Lead
Flashing LED-LH Grille C1826-1	Courtesy of FORD MOTOR COMPANY	Ground
Flashing LED-LH Grille C1827-1		Ground
Flashing LED-LH Front Corner C1705-1		Ground
Flashing LED-RH Front Corner C1707-1		Ground
Flashing LED-LH High Mount C4809-1		Ground
Flashing LED-RH High Mount C4810-1		Ground
Flashing LED-LH Tail Lamp C4412-1		Ground
Flashing LED-RH Tail Lamp C4413-1		Ground
Flashing LED-LH Liftgate C4811-1		Ground
Flashing LED-RH Liftgate C4812-1		Ground

Is the voltage greater than 11 volts?

Yes	GO to C3.
No	REPAIR the circuit.

C3 CHECK FOR GROUND TO THE FLASHING LIGHT-EMITTING DIODE (LED)

Measure:

Positive Lead	Measurement / Action	Negative Lead
Flashing LED-LH Grille C1826-1	Courtesy of FORD MOTOR COMPANY	Flashing LED C1826-4
Flashing LED-LH Grille C1827-1		Flashing LED C1827-4
Flashing LED-LH Front Corner C1705-1		Flashing LED C1705-4
Flashing LED-RH Front Corner C1707-1		Flashing LED C1707-4
Flashing LED-LH High Mount C4809-1		Flashing LED C4809-4
Flashing LED-RH High Mount C4810-1		Flashing LED C4810-4
Flashing LED-LH Tail Lamp C4412-1		Flashing LED C4412-4
Flashing LED-RH Tail Lamp C4413-1		Flashing LED C4413-4
Flashing LED-LH Liftgate C4811-1		Flashing LED C4811-4
Flashing LED-RH Liftgate C4812-1		Flashing LED C4812-4

Is the voltage greater than 11 volts?

Yes	INSTALL a new flashing LED. REFER to the appropriate procedure in this article.
No	REPAIR the circuit.

C4 CHECK THE FLASHING LIGHT-EMITTING DIODE (LED) ZONE

Connect a fused jumper wire:

Positive Lead	Measurement / Action	Negative Lead
C4808A-2	Courtesy of FORD MOTOR COMPANY	C4808A-1
C4808A-3		C4808A-1
C4808A-8		C4808A-1
C4808A-7		C4808A-1

Do the suspect flashing LEDs now operate?

Yes	REMOVE the jumper wire. Verify the lighting relay center or lighting and siren control module 10A output fuses are OK. If OK, GO to C6. If not OK, REFER to the OEM ELECTRICAL WIRING DIAGRAM INTRODUCTION to identify the possible causes of the circuit short.
No	REMOVE the jumper wire. GO to C5.

C5 CHECK THE GROUND TO THE FLASHING LIGHT-EMITTING DIODE (LED)

Measure:

Positive Lead	Measurement / Action	Negative Lead
Flashing LED-RH Front Corner C1707-1	Courtesy of FORD MOTOR COMPANY	Ground
Flashing LED-LH Grille C1826-4		Ground
Flashing LED-RH Grille C1827-4		Ground
Flashing LED-LH Front Corner C1705-4		Ground
Flashing LED-LH High Mount C4809-1		Ground
Flashing LED-RH High Mount C4810-4		Ground
Flashing LED-LH Tail Lamp C4412-4		Ground
Flashing LED-RH Tail Lamp C4413-4		Ground
Flashing LED-LH Liftgate C4811-4		Ground
Flashing LED-RH Liftgate C4812-4		Ground

Is the resistance less than 3 ohms?

Yes	REPAIR the flashing LED voltage circuit.
No	REPAIR the circuit.

C6 CHECK THE CONTROL HEAD

Is the concern still present?

Yes	INSTALL a new communication cable between the control head and the lighting relay center or lighting and siren control module. TEST the system for normal operation. If the concern returns, GO to C7.
No	INSTALL a new control head.

C7 CHECK FOR CORRECT LIGHTING CONTROL OPERATION

For vehicles with lighting and siren control, disconnect and inspect all the lighting and siren control module connectors and jumpers.

For vehicles with lighting control only, disconnect and inspect all the lighting relay center connectors and jumpers.

Repair:
- corrosion (install new connector or terminals - clean module pins)
- damaged or bent pins - install new terminals/pins as necessary
- pushed-out-pins - install new pins as necessary

For vehicles with lighting and siren control, reconnect the lighting and siren control module connectors and all previously disconnected exterior system connectors. Make sure they seat and latch correctly.

For vehicles with lighting control only, reconnect the lighting relay center connectors and all previously disconnected exterior system connectors. Make sure they seat and latch correctly.

Is the concern still present?

Yes	CHECK OASIS for any applicable TSBs. If a TSB exists for this concern, DISCONTINUE this test and FOLLOW TSB instructions. If no TSBs address this concern, CONTACT Whelen Service/Diagnostics at 1-860-526-9504, extension 8308.
No	The system is operating correctly at this time. The concern may have been caused by module connections. ADDRESS the root cause of any connector or pin issues.