So I have found that on the plug,(passenger rear brake light assembly) the (gray with red strip wire) has one pin that has two wires. I have followed the wires to the plastic box (left side rear in the engine compartment). Only one of these wire come out here.
Checking voltage from the driver side to passenger side, and seeing voltage driver side and not passenger side.
So what I am looking for is, where dose that other  (gray with red strip) wire go???
Wiring on driver side to passenger side is the same (different color) but only one wire coming to the back.
Thanks for your help.
Kevin

> Date: Tue, 3 Apr 2012 21:00:28 -0400
> From: plichtakevin@HOTMAIL.COM
> Subject: Passenger running light out!
> To: vanagon@GERRY.VANAGON.COM
> 
> My 91 rear passenger running light dose not come on. Started with bulb then switched plug / socket from drive side.
> Any help, thanks!
> Kevin
>