I was trying to hardwire a power adaptor to run my laptop in my car (I'm on a road trip) and foolishly connected it to a 7.5 amp fuse and grounded the other lead to car body. The power draw for the power adaptor is 6.3 amps, but manufacturer says to mount it on a 15 amp fuse. The fuse in question is unmarked on my fuse panel diagram so i don't know what it does. The car is a 1989 LXi. The 7.5 fuse is mounted just below the under dash fuse panel. Probobly goes to the ECU. None of the fuses are blown. Fuses under the hood all appear to be ok too. I used a fuse tester. Although I was working with battery disconnected, I would connect battery to test. No power to the adaptor when I did the test. The car turns over, but won't start and engine check light stays on. Did I fry the ECU?