What amp fuse should you put on the ignition of your f-150 1989?

There's no single answer to what amp fuse should be in your 1989 Ford F-150's ignition circuit. The correct amperage depends on the total current draw of *all* the components powered by that specific ignition circuit fuse. This varies based on options and added accessories.

You must consult your owner's manual. It will specify the correct fuse rating for each circuit, including the ignition.

Improperly sizing the fuse is dangerous. Too low an amperage, and the fuse will blow constantly. Too high, and you risk a fire if there's a short circuit.

If you don't have the owner's manual, you can try:

* Finding a fuse diagram: These are often located under the hood or inside the fuse box itself. A diagram will show the fuse and its corresponding circuit.

* Checking the existing fuse: The amperage rating is printed on the fuse itself. However, a blown fuse may not indicate the correct amperage; a higher-rated fuse may have been incorrectly used.

* Online resources: Search for a 1989 Ford F-150 wiring diagram or fuse box diagram online. However, be sure it matches your specific truck's trim level and options.

Always replace a blown fuse with one of the same rating. Never use a higher amperage fuse as a makeshift fix.