[s-cars] Help! Blown ECU fuse (what are the probable causes I should inves tigate?)

[James Murray (QB/EMC)]

Paging all guru's and BTDT... any advice for tracking down the cause of a blown ECU fuse? I'll keep searching the archives but so far I came up empty. My car is a 93 S4. 

Yesterday (during the day), while in reverse the car suddenly died, tried restarting multiple times... nada. Scrambling to get her out of the way of blocking traffic I slightly cracked my rear middle driver side tail light in the process... don't ask it was a really really dumb ass move on my part (brain fart I guess), anyone have a replacement they could sell me? Anyway, car turns over fine, everything appears to work, but she wouldn't start!? So the possible causes start to run through my head as I sat there stranded... 

Checked all fuses on driver's side (maybe it's the fuel pump), nope all are ok. A little low on gas, maybe the remaining gas is bad? - not likely as it should at least run rough, run to get a fresh can of gas anyway just to be safe, nope didn't work.  Ok time to check for a spark, pull the coils out and low and behold there's no spark! Ok what could cause this I thought... Camshaft Positioning Sensor - oh crap not this again I thought, but damn it I replaced that 1.5 years ago... ok re-set the plug anyway just to be safe... grab a piece of wire to pull to activate the codes and start  reading the check engine light. Hey wait a minute there's no check engine light... that's strange ! Ah damn the thing must have burnt out. Of course it wasn't after a lot of frustration that I realized it was too much coincidence that the check engine light burnt out, so I started from there... luckly I was close enough to walk to the office and search on SJM site (hmmm look at that the ECU is !
 fused). I pulled the carpet out and low and behold the damn ECU fuse had blown !!! what the hey? what could have caused this? 

Is it possible there's a pinched wire someplace? I recently had the front bearings and tie rods changed and I changed the driver door handle cable replaced, so I had the driver side door apart. I can't think of anything that could cause this with respect to the very recent repairs, but you never know. 

Thanks for listening... 

Cheers, /James.

P.S. What was Audi thinking putting a fuse in a location you can't check, and have to cut the carpet to get to it... of course it's not suppose to blow, but that's what fuses are for... just in case! 

BTW: So I know how to check for spark on these cars, how do you check if you have fuel delivery if stranded? (for future reference)