Answer
Jul 22, 2025 - 09:50 AM
Wiring the ignition switch on a Ford 1900 tractor depends on whether it's the original switch or an aftermarket replacement, but here’s a general rundown of what each terminal usually connects to:
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BATT (Battery/Power In) – This terminal gets direct power from the battery. It’s often a thick red wire.
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IGN (Ignition/Run) – Sends power to the ignition system and accessories when the key is in the "ON" position.
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ST (Start) – This terminal powers the starter solenoid when the key is turned to "START".
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ACC (Accessory, optional) – Sometimes used for accessories like lights or radios (not always used on tractors).
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GND (Ground, if present) – Some switches use this to complete a circuit for a warning buzzer or indicator.
Basic steps:
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Disconnect the battery before starting.
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Identify wires using a wiring diagram or by tracing them to their components.
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Connect battery power to BATT.
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Connect the ignition wire (to coil or fuel shutoff) to IGN.
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Connect the starter solenoid wire to ST.
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Reconnect battery and test.
If you’re unsure about wire colors or terminal markings, it’s a good idea to consult a wiring diagram specific to the Ford 1900. I'd suggest you grab this 👉🏻 Ford 1900 Tractor Service & Repair Manual, which contains every repair procedure and wiring diagram provided by Ford.
