One problem related to underhood wiring has been reported for the 2001 BMW X5. The most recently reported issues are listed below.
Contact statd BMW X5 2001 caught on fire on July 21, 2005. The temperature gauge was at hot, the car started to lose power, the tachometer was over 4 and white smoke started to come out of the engine area while he was driving the car on the highway going approx. 30 mph. As the smoke got worse, he pulled off and the smoke became very white and dense and then ignited into a fire. The fire dept. Did come out. The fire did originate from under the hood. Prior to this he had no problems with the car heating up. The car was totaled.