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Data Link References

WARNING: This page is about a different car, the 2004 Pontiac Aztek and 2004 Buick Rendezvous. However, it is still accessible from the selected car via links, so may be relevant.

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 .

Data Link References

Control Module Data Link Type Diagnostic Procedure
Schematic Reference: Data Link Connector (DLC) Schematics 
BCM Class 2 Refer to Scan Tool Does Not Communicate with Class 2 Device 
EBCM Class 2 Refer to Scan Tool Does Not Communicate with Class 2 Device 
Engine Control Module (ECM) High Speed GMLAN/Class 2
HUD Class 2 Refer to Scan Tool Does Not Communicate with Class 2 Device 
Instrument Panel Cluster (IPC) Class 2 Refer to Scan Tool Does Not Communicate with Class 2 Device 
PASS-KEY Module Class 2 Refer to Scan Tool Does Not Communicate with Class 2 Device 
PCM Class 2 Refer to Scan Tool Does Not Communicate with Class 2 Device 
Radio Class 2 Refer to Scan Tool Does Not Communicate with Class 2 Device 
SDM Class 2 Refer to Scan Tool Does Not Communicate with Class 2 Device 
Transmission Control Module (TCM) High Speed GMLAN Refer to Scan Tool Does Not Communicate with High Speed GMLAN Device