Volvo Repair: 1995 Volvo 850 dead, reading equipment, volvo 850

Question
I have above average mechanical skills. The car has 85000 miles. The car was running well and had recently averaged 28 mpg on a trip from Portland to Bozeman and back. The engine will crank but not start. There is no spark. The fuel pump does not run. The ECU (Motronic 4.3) will not respond to queries placed through the test port A-6. When I press the test button for 1 sec. the LED will light (while pressed) but not return any codes. I have checked most of the various power sources with the exception of the main relay (2/32). Is the only option at this point a bad ECU or have I missed some testing along the way other than relay 2/32. I am using Alldatadiy as my main source of information along with Haynes and a few other bits and pieces I have collected. Thank you for your insight.

Answer
Hi Gordon,
      My ability to fully grasp all the test procedures you've gone through is giving me a ever so slight headache.
          I'd take car to dealer for their diagnosis...often after market code reading equipment needs updates or recalibration...especially if dropped.
             Not to take away from your ability,you may want another hands on opinion.
            
                Good luck,
                         Bilbo