Fuse 21 blown

[Frank Z]

99, 4.0l, AW4
Been strughli g sith this for a few days, tme to see what everyone thinks.

As soon as I turn the ignition on the fuse blows.

Already replaced the coil a couple hundred miles ago. I've also replaced the PCM.

I've unplugged all of the injectors, sensors and even the fuel pump.....still blowing the fuse immediately.

Any thoughts?

 

[Blazair]

I had a similar situation with Fuse 21. I swapped out the horn relay (it was clicking when I hit the horn button), but I swapped it out anyway and seems to have fixed the problem.