Sounds to me like it's the relay under the dash. It's a bit of a PITA to get to. I replaced mine last year and have to do it again...
http://automotivetool.wordpress.com/2009...just-park/
http://automotivetool.wordpress.com/2009...just-park/
2003 Focus ZX5 Racecar/Perma broke/Storage
2011 Volkswagen Jetta Daily Driver
2011 Volkswagen Jetta Daily Driver