2006 Corvette making squeaking noises
Safety Car
Joined: Dec 2006
Posts: 4,587
Likes: 1,667
From: Pearland / Houston Tx
Misc info:
TSB #08-07-30-021B
Loss of High Speed GMLAN Communications, Intermittent No Crank, IPC Gauge Fluctuation, Intermittent Door Lock Cycling, Transmission May Not Shift, DTCs U0073, U0100, U0101, U0102, U0121, U0140 Set - (Sep 8, 2008)
Cause
These conditions may be caused by a terminal for the High Speed GMLAN Serial Data Bus that has backed out of the 16-way electrical connector to the automatic transmission
DTC U0073 or U2100
Circuit Description
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. 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.
DTC Descriptors
This diagnostic procedure supports the following DTCs:
• DTC U0073 Controller Area Network (CAN) Bus Communication
• DTC U2100 Controller Area Network (CAN) Bus Communication
DTC Descriptor
DTC P0700: Transmission Control Module (TCM) Requested MIL Illumination
Circuit/System Description
The transmission control module (TCM) uses the (GMLAN) to signal the engine control module (ECM) that the TCM is requesting malfunction indicator lamp (MIL) illumination. This happens when the TCM has determined that a failure affecting emissions has occurred in transmission control system. When the ECM receives the a message from the TCM, DTC P0700 will set.
TSB #08-07-30-021B
Loss of High Speed GMLAN Communications, Intermittent No Crank, IPC Gauge Fluctuation, Intermittent Door Lock Cycling, Transmission May Not Shift, DTCs U0073, U0100, U0101, U0102, U0121, U0140 Set - (Sep 8, 2008)
Cause
These conditions may be caused by a terminal for the High Speed GMLAN Serial Data Bus that has backed out of the 16-way electrical connector to the automatic transmission
DTC U0073 or U2100
Circuit Description
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. 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.
DTC Descriptors
This diagnostic procedure supports the following DTCs:
• DTC U0073 Controller Area Network (CAN) Bus Communication
• DTC U2100 Controller Area Network (CAN) Bus Communication
DTC Descriptor
DTC P0700: Transmission Control Module (TCM) Requested MIL Illumination
Circuit/System Description
The transmission control module (TCM) uses the (GMLAN) to signal the engine control module (ECM) that the TCM is requesting malfunction indicator lamp (MIL) illumination. This happens when the TCM has determined that a failure affecting emissions has occurred in transmission control system. When the ECM receives the a message from the TCM, DTC P0700 will set.
