Ignition/starter switch

2004 FORD F-150

102,000 MILES • V6 • 2WD • AUTOMATIC

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Park the truck, turn ignition switch to off position and pulled out the key. Engine keeps running with the key pulled out. Reinsert ignition key in, would turn from off to run position, turn smoothly and do not feel any restraint and the engine still running. Unhook battery cable but engine still running, need to pull out 30Amp fuse to shut-off engine.

Sep 17, 2018 at 8:07 AM

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Hello,

It sounds like the PCM relay is stuck on. Here is a guide and the engine wiring diagrams so you can see how the system works and the relay location under the hood as well (203):

https://www.2carpros.com/articles/how-to-check-an-electrical-relay-and-wiring-control-circuit

Check out the diagrams (below). Please let us know what you find. We are interested to see what it is.

Cheers, Ken

Images (Click to enlarge)

Sep 18, 2018 at 12:18 PM