Replace a worn or damaged switch plug with the Standard Ignition Hazard Warning Switch Connector / Headlight Dimmer Switch Connector, part number S-621. It fits many vehicles, among them the 1985-1991 Ford F-150, 1985-1991 Ford F-250 and 1979-1989 Ford Mustang. It is a direct-fit replacement for the listed applications; see the "Vehicles it fits" section for the full list. This connector is cataloged under both names: hazard warning switch connector and headlight dimmer switch connector.
- Built to OE standards: Standard Ignition manufactures its components to meet exact OE standards in facilities certified to TS16949 and ISO9001, and designs them for specific vehicle applications.
- Tested throughout production: Each connector goes through thorough quality checks and rigorous testing at every stage of manufacturing.
- Factory-assembled: The connector arrives assembled, with wire connectors and extended lead wires included where applicable.
- No specialized tools: The user-friendly design is intended to simplify installation without the need for specialized tools.
A switch connector joins the vehicle's wiring to the switch. Signs it may need replacing include a cracked, melted or corroded connector housing, loose terminals, or intermittent headlight beam or hazard flasher operation. The switch itself or other wiring can cause the same symptoms, so diagnose the cause before replacing the connector.
Interchange: 419 · EC114 · 88860493
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Frequently Asked Questions
What does the Standard Ignition S-621 connector do?
It is the electrical connector for the hazard warning switch / headlight dimmer switch, joining the switch to the vehicle wiring on the listed applications.
Is this the right Mustang switch connector for my 1979-1989 Ford Mustang?
Yes. S-621 is listed as a direct-fit application for the 1979-1989 Ford Mustang. The "Vehicles it fits" section has the full fitment chart.
Does it fit the 1985-1991 Ford F-150 and F-250?
Yes. The 1985-1991 Ford F-150 and the 1985-1991 Ford F-250 are both listed applications. See the "Vehicles it fits" section for the other vehicles.
What comes with the connector?
It arrives factory-assembled, with wire connectors and extended lead wires included where applicable. It is designed to install without specialized tools.
What are signs the switch connector may need replacing?
Signs include a cracked, melted or corroded housing, loose terminals, or intermittent headlight beam or hazard flasher operation. Diagnose first, because the switch or the wiring can cause the same symptoms.
