Rear turn signals don't work right on 1995 Cadillac Seville SLS

My turn signals flash weird on the rear of my 95 Seville SLS. They alternate from inboard to outboard. When headlights are on the flash fast for both sides. Any Ideas? Does anyone have a good wiring schematic? Thanks

Here are two online sources for you:
For AllData:
Here's the one for Mitchell as well:
I appreciate it. Im sure it will get me what need.