[TazRango]

Try unplugging the trailer wire harness from taillights. If front blinker is working, and no problem with other side then the relay is just fine.

If it's a factory tow package, then it won't be spliced in by the tail lights - which considering he said the green/red wire is dead is probably the case.. Also, the combination flasher in an 02 has separate outputs for front and rear, so the front working means nothing.
@Burned - you most likely will not be able to repair the flasher. It's a solid state unit that basically just contains a relay to make it 'click'. Does the left brake light come on?

 

[TazRango]

Well that's good news! Since you've obviously got electronics experience, is there any chance you can pick over it and see if there's any simple modification you can do to completely disable the hyper-flash (for those who want to switch to LEDs so they don't have to use resistors)?