The other morning I was on my way to work when all of a sudden my truck shut down. I pulled of to the shoulder off the highway (bad spot on highway) I called the old lady to come up and bring some tools that I needed. The truck would turn over but not start. I pulled the alternator took it to the part store and got it tested two different places and passed both times. The battery checks out good. By this time it is rush hour so I decide to get it towed home. My buddy comes over and he has a spark plug tester and I am not getting and spark. I checked the ingtion module thing they all got power. I have double checked all fuses and i dont know what else to look at. It turns over just wont fire up. Any ideas thank you in advance! (the battery light came on after all this happend) no check engine light

Scott