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Sequential Turn Signal Unit - NOS ~ 1970 - 1973 Mercury Cougar

Item #: 25782
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Price: $252.86
    The product is in stock Availability*: Out of Stock
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    This product is an NOS Part. NOS items are OEM parts from Ford that have been sitting on shelves or in warehouses for years. These are often great examples of the orignal parts, but they may have scratches or other shelf wear.

    However be aware that some NOS parts are "service replacement" parts. "Service replacement" parts are not exact replacements of the parts that were installed at the factory, but are what Ford considered as "good enough" and were used at Ford dealerships after the original supply of parts was exhausted.

    We often leave NOS product listings on our website after they sell for reference purposes.

    NOS sequential unit for the taillights of the Mercury Cougar

    Ford part # D1WY-13A366-A.

    1971 Cougars built from 2/1/71 to 5/15/71 used a unique sequential system in the trunk, D1WY-13A366-C. It uses two connectors, grey and light blue, that are no longer serviced. When the sequential system must be serviced, it can be replaced by an NOS unit, or a replacement unit, such as the C9WY-13A366-AL sequencer shown below. Since these unique connectors are no longer available, the connector plugs on the tail light harness must be replaced with the more typical red and black plugs. The C9WY-13H366-AR harness connector repair kit provides these plugs along with about 12” of wire for splicing. Installation requires cutting off the old grey connectors and splicing on the new red/black connectors while matching up the wire color codes. Slide heat shrink tubing over each wire and solder (no butt splices) each connection. Wrap the bundle with electrical tape to protect the connections. Remove the old sequential system board from the black case, install a new C9WY-13A366-AL sequential system board and plug into the harness. Replace the turn signal flasher can with a D0WY-13A366-AR when using 1157 bulbs or a D0WY-13A366-L flasher when using LED bulbs. Remember to test both the turn signals and brake lights prior to driving the car.



    *NOTE* Need help diagnosing a Cougar turn signal problem? Victor Yarberry is the world’s most knowledgeable expert on the subject. Vic has owned Cougars since the 1970's and is the designer of all of our solid state sequential systems. There is no question he cannot answer! Here is a link to a great source of information on the subject.

    Shipping Weight:
    2.00 LBS
    (weight shown may be the dimensional weight)
    Shipping Dimensions:
    Number of questions: 0

    Why am I being warned about potential exposure to chemicals in motor vehicle parts?


    • Some chemicals in motor vehicle parts are on the Proposition 65 list because they can cause cancer and/or birth defects or other reproductive harm.
    • When purchasing USED or NOS items, we do not know if listed chemicals are present in these products.
    • This product is known to contain the following listed chemicals:

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