Pinpoint Test C: One High Beam Headlamp Is Inoperative
WARNING: This page is about a different car, the 2009 Mercury Grand Marquis and 2009 Ford Crown Victoria. However, it is still accessible from the selected car via links, so may be relevant.
- C1 CHECK THE LOW BEAMS
- Key in OFF position.
- Place the headlamp switch in the HEADLAMPS ON position.
- Do the low beams operate correctly?
NOTE: Make sure the multifunction switch is in the LOW BEAM position.- YES : Go to C2.
- NO : Go to Pinpoint Test B .
- C2 CHECK THE HEADLAMP VOLTAGE SUPPLY CIRCUIT FOR AN OPEN OR SHORT TO GROUND
- Disconnect: Inoperative Headlamp
- Disconnect: LCM C2145c
- Measure the resistance between the inoperative headlamp, harness side and the LCM, harness side; and between the inoperative headlamp, harness side and ground as follows:
Vehicle Inoperative Headlamp Connector-Pin LCM Connector-Pin Circuit Crown Victoria C1021-3 (LH) C2145c-16 1337 (VT/YE) C1041-3 (RH) C2145c-15 1335 (YE/WH) Grand Marquis C1284-3 (LH) C2145c-16 1337 (VT/YE) C1285-3 (RH) C2145c-15 1335 (YE/WH) - Is the resistance less than 5 ohms between the headlamp and the LCM, and greater than 10,000 ohms between the headlamp and ground?
- YES : Go to C3.
- NO : REPAIR the circuit in question. TEST the system for normal operation.
- C3 CHECK FOR CORRECT LCM OPERATION
- Disconnect all the LCM connectors.
- Check for:
- corrosion
- damaged pins
- pushed-out pins
- Connect all the LCM connectors and make sure they seat correctly.
- Operate the system and verify the concern is still present.
- Is the concern still present?
- YES : INSTALL a new LCM. REFER to MULTIFUNCTION ELECTRONIC MODULES article. TEST the system for normal operation.
- NO : The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector.