I have had my 02 Duramax since new and love it, the only problem so far is at elevations above 4000', some times my check engine soon light comes on with the computer code of 540 which is air intake heater circuit malfunction. Has anyone else had this problem? I have had it checked by dealer and they erase the code and can not duplicate this problem. Elevation here aprox. 350'

Dick,
Still have the 540 problem? I do and I'll have to replace the circuit. About $240.00 at the dealer.
Mike