Blow Signal Fuse

[Shasan]

I need help 1994 mustang gt convertible when set shifter on reverse gear why blow my signal fuse

 

[jozsefsz]

There are quite a few wiring problems that can cause that fuse to blow, generally something is shorted in that circuit. This thread has tons of great information on troubleshooting and repair.

Fuse # 1 Keeps blowing when car is put into reverse | Mustang Forums at StangNet

In this case, it turned out to be the reverse (backup) switch on the transmission.
Modern Driveline Mustang Back Up Switch T5/T45 Transmission