ADCIN giving inconsistent results

[triton99]

After a few weeks of work and family things, I finally found the time to complete the project. The ACDIN results were inconsistent at first, but I etched a new board and instead of SMD components I used thru-hole. The new board worked perfect on the bench but failed on the car...until I realized I had used a NPN transistor instead of an PNP. Before I realized this I made a small relay board that the transistor would switch, which would then turn on the cooling fans. I salvaged the relay from an old TRS-80 motherboard that was ruined. Once the transistor was swapped out and the relay board added, everything worked perfect. We took some test runs, and the cooling fans turned on/off as expected. When the transistors were switched I also had to reverse the high/low settings on the relay outputs on my board. My personal blog has a little more info. http://triton9.wordpress.com/
Thanks again to everyone for all the help!!