1990 Mustang signal lights not working

The fuse panel diagram indicates that cavity #5, which is a 15A fuse that protects the turn signal lamps, backup lamps, fluid module and heated rear window relay. I'm going to check the other things that this fuse protects and see if they're working, since if this fuse was blown nothing else in that circuit should work either.

OK, so I pulled fuse #5 and found that it was blown. I replaced it with another 15A fuse and started the car. Tried the signal lights and they worked. Perfect. I let the car idle for a minute and began to drive, but by the time I had to use the signal light, it was not working again.

I never used the rear defroster, so that never blew the fuse, I never shifted into reverse, so that didn't do it, and I already tried out the signal lights and they worked for the time that they were activated. The only other thing protected by that fuse is something called the fluids module. Interestingly enough, the car has been sputtering and poping after making a turn since this problem has been there. I'm guessing they could be related??

Does anyone know what a fluids module is, what it does and/or where it's located? This might be the source of my problem.