Headlights don't work unless you hold high beams

SOURCE: Headlights don't work

Try replacing the bulbs in the sealed beam. Bulb #9007, do both. Lift lid, disconnect electrical wires, unlock o ring, pull out bulb. Replace bulb and reverse the order

SOURCE: No headlights, they work if I hold the high beam/wiper arm back

If you have an AUTO off/on/delay this could be malfunctioning, you may also need a need headlight switch however, First check your low beam halogen bulbs if they are bad replace BOTH at the same time they tend to fail at a similar time and this is the least costly repair NOTE wen changing these do not touch bulb with bare hand as oils from your skin can cause the to heat unevenly and explode inside your headlight assembly Use rubber gloves most Parts stores have these available for this reason

SOURCE: Headlights do not work

It cost me just under $700.00 to have a dealership replace the headlight control module.

SOURCE: 2004 grand marquis headlights won't come on

Just had my 2004 Grand Marquis HL fixed. They would go off after less then 5 mins and then come back on in less than 5 mins. Then repeat. ONLY The high beam Hold switch would work. It was the LCM (Light Control Module) found behind the Glove Box. $700 for the Dealer to fix.
15 Min job for anyone who can figure out
how to remove the Module.

SOURCE: headlights turn off while driving.

Hi,

These vehicles have alot of problems with the light control module which is most likely the cause. While the problem is occurring, check fuses 6, 15, 21, 23, and 27 in the inside fuse box. Fuses 21, 23, and 27 should be hot at all times, and fuses 6 and 15 should be hot with the key on. If OK, access the Lighting Control Module (LCM), under the dash, to the passenger side of the steering column. Disconnect connector C2145b (16-terminal connector with round, pin-type terminals) from the LCM. Jump battery voltage to the Gray wire in pin 10 of C2145b, and see if the headlights come on. If not, repair the open Gray wire between the LCM and the multifunction switch. If the headlights come on when power is jumped to the Gray wire, locate LCM connector C2145c (16-terminal connector with spade-type terminals), and check for battery voltage on the White/Violet wire in pin 1 of C2145c (from fuse 15), and battery voltage on the Red/Yellow wire in pin 9 of C2145c (from fuse 6). If OK, go to connector C2145b, and check for battery voltage on the Tan/White wire in pin 12 (from fuse 21), battery voltage on the Light Green/Yellow wire in pin 1 (from fuse 23), and battery voltage on the Orange/White wire in pin 6 (from fuse 27). Check for good grounds on the Black wires in pins 4 and 9 of C2145b (grounding to G201, behind the passenger side kick panel). If the LCM power and grounds are all OK, turn the headlight switch on, and check for ground from the headlight switch on the Red/Yellow wire in pin 10 of C2145c (This is the wire that should be grounded by the headlight switch with the switch in the "normal" headlight position). Also check the Tan/White wire in pin 3 of connector C2145a (the 22-terminal LCM connector). This wire should NOT be grounded except with the switch on the OFF position. If OK, reconnect the connectors, verify that the problem is still present, and if so, replace the LCM.

Module is often a problem, i could say atleast 90%.

The module is a little expensive. they are about $520. You can also locate a used one from local salvage yards. But I would recommend having your local dealership test it to make sure before you spend $520.You could also check few online stores which would have this part available at less price.Dealers usually have a high mark up on the parts.

Let me know,if needed further assistance.

Hope i helped you.

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