Bavism: I just ordered that yesterday and messed around with FORscan. Seems like it'll do everything I need for tracking down my very intemittent advancetrac/abs issue.
Plus, for 5 bucks you can download the app on an android device if you don't want to lug a laptop in the passenger seat while driving. My work laptop has bluetooth so i'm just gonna use that vs the app.
Good stuff. Had a thread up for over a week on FTE and nothing, come here? WAY more info on expys. Great site
OP: When i got my 04 recently it had the little problems and one was the back up aid. Simple task(for me), turn ignition on, put in Reverse, step out and listen closely to each sensor. The one that isn't clicking? That's the bad one. You can move them around to determine if it's wiring or the sensor. For me it was just a sensor.
4 for 30 bucks on ebay. Work and look EXACTLY like oem. Good luck, it shouldn't give ya much grief. Also, the back up sensors do come in handy if you use your expy like mine for roadtrips. Went to chicago and the parking is TIGHT. Sensors helped out quite a bit and were well worth the 5 minutes of troubleshooting/installation and the 30 bucks for a brand new set.
I didn't replace all 4, got 3 spares inc ase another bites the dust.
Have a good one