Grand Marquis V8-4.6L Flex Fuel (2010)
Daytime Running Lamp: Pinpoint Tests
Daytime Running Lamps (DRL)
Pinpoint Tests
Pinpoint Test AE: The Daytime Running Lamps (DRL) Are Inoperative
Normal Operation
When the ignition switch is in the RUN position, the headlamps are not on (from the autolamp system or manual control from the headlamp switch) and
the transmission is not in PARK (P), the Lighting Control Module (LCM) provides a pulse-width modulated voltage to the low beam headlamps. This
illuminates the headlamps at a reduced intensity.
This pinpoint test is intended to diagnose the following:
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Exterior lighting system input/output
-
LCM configuration
-
Ignition switch input
-
Transmission gear input
-
LCM
PINPOINT TEST AE: THE DRL ARE INOPERATIVE
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AE1 VERIFY THE DRL OPERATION
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Ignition ON.
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Place the gear selector lever in any gear other than PARK (P).
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Are the DRL illuminated?
Yes
The system is operating correctly. INFORM the customer of the conditions required for the DRL to operate correctly.
No
GO to AE2.
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AE2 CHECK THE OPERATION OF THE HEADLAMPS
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Place the headlamp switch in the HEADLAMPS ON position and observe the headlamps.
-
Do the headlamps operate correctly?
Yes
GO to AE3.
No
REFER to Headlamps See: Headlamp/Testing and Inspection.
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AE3 CHECK THE IGNITION SWITCH INPUT
-
Place the headlamp switch in the OFF position.
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Enter the following diagnostic mode on the scan tool: LCM DataLogger.
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Monitor the LCM ignition switch PID (IGN_LCM) while cycling the ignition switch through all positions.
-
Does the PID agree with the ignition switch positions?
Yes
GO to AE4.