Join Date: Oct 2011
Location: Magnetic Hill, New-Brunswick
U codes mean a lost of high speed GMLan. Your P codes are probably bogus because you lost GMlan communication and will probably go away after. If it's not your ground wire under the seat you will find a broken wire somewhere.
The GMLAN serial data circuits are controller area network (CAN) high and/or low speed serial data buses used to communicate information between the control modules. Typical data transmission speeds must be high enough to ensure that a required real-time response is maintained. There are two different types of GMLAN serial data circuits, the High speed 2-wire circuit and Low speed single wire circuit. Refer to Data Link References for the complete description of the buses used on this vehicle. The GMLAN serial data circuits also communicate directly to the data link connector (DLC). Messages are interpreted by the externally connected CANdi module which acts as a transceiver for the scan tool.
Modules connected to the GMLAN serial data circuits monitor communications during normal vehicle operation, where operation information is exchanged among the modules. All the modules on the GMLAN networks, maintain a transmit error counter (TEC) and a receive error counter (REC). The counter values increase with detected errors and will decrease with error-free messages. If the TEC value exceeds 255, the controller removes itself from the network and DTC U0073 will result.
U0101 Lost Communication with Transmission Control Module (TCM)
Ica list your P codes if you want but don't think they're important at this time....
Never drive faster than your guardian angel can fly
Last edited by Coby7; 04-24-2014 at 03:36 PM.