[dana44]

That isn't a turn signal problem, that is a brake light switch problem (more than likely). Imperials are more of a C body, but the brake light switch should be on a bracket along the edge the brake pedal would contact. Flashing on the front but not the back would be associated with a broken or loose wire so they need to be traced from the switches and back to the tail. They should run to the foot dimmer switch, behind that kickpanel, under the sill/along the sill of the driver side to the trunk. They are usually protected with a tin shield to the trunk, but things happen. Time for a wiring diagram, too.

 

[dana44]

My bad, didn't think about it that way. A volt meter would be able to verify circuitry working easier than trying to remove it to test. Just trying to help the guy out and diagnose easier.

 

[dana44]

This is starting to sound like some melted wires somewhere going to the trunk. I had a similar problem with a bulb removed in my tailights and shorting the wiring harness, melting a couple wires together and then cross shorting all over the place, but still functioning, so to check and verify this, look at the plug connections (they usually get the hottest and will melt), and if there is any warping or melting, then start checking the wires themselves. All the wires are interconnected with the headlight switch, brake light switch, turn signal, dimmer switch (they like to corrode and ground out there, too), and dash lights, so it can be pretty overwhelming where the problem really starts. Wires sticking to each other is a big indicator of a problem. I redid my dash harness and was lucky enough to find the melted and fused wires before I connected the battery and having the same problem.

 

[dana44]

Well, in doing two things at the same time, pumping brakes and turning turn signal arm, you need to isolate one at a time to figure out which is the bad item.