Replacing the faulty factory relays with a new standard 5-pole external relay is the next step in fixing the headlight failure for your Ford/Mercury LCM.The LCM is located under the driver-side foot well above the gas pedal. Disconnect the three wiring harnesses, two screws, and push the tang to slide it out of its bracket. The box can be opened by pressing the tangs down folding the top on its hinges.
Locate the faulty relay on the inside of the LCM board as shown. You might notice a yellow discoloration or it may look overheated--that's because it was. All the headlight amperage flows through that tiny relay. All five contacts must be carefully de-soldered from the back of the board. (Be very careful. The board is very thin, the integrated printed circuits are very thin, and the you need a steady hand.) New small gauge wire (22 gauge) can then be re-soldered to the board and extended outside the LCM box. Label each wire for the five contacts (30, 85, 86 87 and 87a as shown). The new relay can be attached outside the box and zipped tied in place. It will now handle the job of the former tiny under-build factory relay.
Alternately, you can solder in a new replacement mini-relay. My research shows they are very hard to find, horribly back ordered, and the shipping for these tiny $4 relay makes them prohibitively expensive, thus the standard relay fix. Here are the part numbers: NEC part # EQ1-11111S or the better replacement NEC part #MR301-12HSL. Try Omni-pro.com or Mouser.com.
Next: More LCM fix/replacement options.
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