Well, I just got back from my buisness trip and no fault light came on the whole way up and back from the airport (about 160 miles round trip), so I'm thinking its some RF interference from the DVD player we were using on the trip, although I don't know how it would cause it.
Do remote controls transmit even if they are not being used?? The remote for the DVD system was sitting in one of the rear cup holders on the center console. What about radiated EMI from the physical player and screen? (its a self contained screen/DVD player that straps on the headrests, and a second screen is connected via wire to the "master" unit)
Thanks for the replies so far...