1994 Acura Integra No Power to car

I just bought this car and everything was working great when I bought it. I brought it home and noticed that the electrical connections to the battery were corroded so I took them off, cleaned them and reinstalled. NOW NOTHING WORKS! The headlights work, horn, heater fan but nothing else. There is an alarm installed. I checked underhood fuses by checking continuity, the battery is at 11.8v, I checked the ground to the battery by putting pos (of voltmeter) on battery and neg on engine block and got 10.8v. I have the wiring diagram for the car and everything works thats before the 100amp main fuse, but that fuse "seems" to check out. I tried 2 sets of keys. I hear a relay click when I turn the key but no dash lights come on. I dont understand, im going to continue to look at the wiring harness but how could this happen? All I did was clean the connections. Dead ecu? Alarm immobilizer? Fried harness? Ground somewhere? Bad battery?