My neighbour discovered this. I didn’t believe him, so he hauled out the manual to prove it.

Turn to page 44 in your Ford F150 manual (don’t know if this works on older models.)

Note the two front seats must be done independently.  And this won’t work if you’re using a Ford MyKey.

Before starting:

– ignition is OFF
– truck is in Park (P)
– the parking brake is ON
– both front seat belts are unbuckled

Follow these steps:

1 – turn the key, but not all the way to start the engine

2 – wait about 1 minute until seat belt warning light goes off. Once off, wait 5 more seconds before starting step 3

You must complete steps 3 – 4 within 30 seconds.

3 – buckle and unbuckle the belt 3 times. End in unbuckled position. The warning light will turn on.

4 – With the light on, buckle then unbuckle again. The light will flash for confirmation.

Do it all again to turn the chime back on.

I canNOT believe this exists.