For 1990-2009 cars

This table identifies which serial data link that a particular module uses for in-vehicle data transmission. Some modules may use more than one data link to communicate. Some modules may have multiple communication circuits passing through them without actively communicating on that data link. This table is used to assist in correcting a communication malfunction. For the description and operation of these serial data communication circuits refer to Data Link Communications Description and Operation .

Control Module | Data Link Type | Diagnostic Procedure
--- | --- | ---
Schematic Reference: Data Communication Schematics
Audio Amplifier | Low Speed GMLAN | Scan Tool Does Not Communicate with Low Speed GMLAN Device
Driver Door Module (DDM) | Low Speed GMLAN | Scan Tool Does Not Communicate with Low Speed GMLAN Device
Driver Door Switch (DDS) | Low Speed GMLAN | Scan Tool Does Not Communicate with Low Speed GMLAN Device
Dynamic Headlamp Leveling (DHL) Device, w/TR7 | High Speed GMLAN | Scan Tool Does Not Communicate with High Speed GMLAN Device
Driver Position Module, w/A45 | Low Speed GMLAN | Scan Tool Does Not Communicate with Low Speed GMLAN Device
Electronic Brake Control Module (EBCM) | High Speed GMLAN | Scan Tool Does Not Communicate with High Speed GMLAN Device
Electronic Suspension Control (ESC) Module, w/F55 | High Speed GMLAN | Scan Tool Does Not Communicate with High Speed GMLAN Device
Engine Control Module (ECM) | High Speed GMLAN | Scan Tool Does Not Communicate with High Speed GMLAN Device
HVAC Control Module | Low Speed GMLAN | Scan Tool Does Not Communicate with Low Speed GMLAN Device
Instrument Panel Cluster (IPC) | Low Speed GMLAN | Scan Tool Does Not Communicate with Low Speed GMLAN Device
Instrument Panel Module (IPM) |

• | High Speed GMLAN

• | Low Speed GMLAN

Scan Tool Does Not Communicate with High Speed GMLAN Device

Inflatable Restraint Sensing and Diagnostic Module (SDM) | Low Speed GMLAN | Scan Tool Does Not Communicate with Low Speed GMLAN Device
Left Rear Door Module (LRDM) | Low Speed GMLAN | Scan Tool Does Not Communicate with Low Speed GMLAN Device
Passenger Door Module (PDM) | Low Speed GMLAN | Scan Tool Does Not Communicate with Low Speed GMLAN Device
Radio | Low Speed GMLAN | Scan Tool Does Not Communicate with Low Speed GMLAN Device
Rear Integration Module (RIM) | Low Speed GMLAN | Scan Tool Does Not Communicate with Low Speed GMLAN Device
Remote Control Door Lock Receiver (RCDLR) | Low Speed GMLAN | Scan Tool Does Not Communicate with Low Speed GMLAN Device
Right Rear Door Module (RRDM) | Low Speed GMLAN | Scan Tool Does Not Communicate with Low Speed GMLAN Device
Television Module, w/YQ6/YQ7 | Low Speed GMLAN | Scan Tool Does Not Communicate with Low Speed GMLAN Device
Transmission Control Module (TCM) | High Speed GMLAN | Scan Tool Does Not Communicate with High Speed GMLAN Device