Recently, while driving, my door locks unlocked and then relocked without being envoked manually. This has occurred several time at different speeds while accelerating and decelerating. On occasion, the air conditioning system is turned off. On two occasions, the engine cut out. This obviously is of most concern to me as the steering wheel locked up. To recover, I quickly placed the transmission in neutral and restarted the engine. I took my Tahoe into the Chevy dealer but the mechanics were unable to find the source of the problem after running the diagnostics. I was certain that this was related to a falty computer chip. Now, I am at a loss for what is causing the locking system to operate unprovoked. Has anyone else experienced this dilemma? Thanks for you input in advance.