Class 2 Serial Data Line
WARNING: This page is about a different car, the 2003 Oldsmobile Bravada, 2003 GMC Envoy XL, 2003 GMC Envoy, and 2003 Chevrolet TrailBlazer. However, it is still accessible from the selected car via links, so may be relevant.
The class 2 serial data line on this vehicle is a star configuration. The PCM has an additional class 2 serial data circuit to BCM or to theft deterrent control module, if equipped. If one of the class 2 serial data circuits to the PCM opens, communication will not be interrupted. The following modules communicate on the class 2 serial data line:
- The audio amplifier
- The body control module (BCM)
- The driver door module (DDM)
- The electronic brake control module (EBCM)
- The front passenger door control module (FPDM)
- The HVAC control module
- The inflatable restraint sensing and diagnostic module (SDM)
- The instrument panel cluster (IPC)
- The liftgate control module (LGM)
- The memory seat module-driver, w/power seat
- The memory seat module-passenger, w/power seat
- The powertrain control module (PCM)
- The radio
- The RSA/HVAC control module-rear auxiliary
- The theft deterrent control module, for export
- The transfer case shift control module, w/4WD
- The vehicle communication interface module (VCIM), w/UE1
The class 2 serial data line allows a scan tool to communicate with these modules for testing purposes, checking for DTCs, and to activate/enable/disable functions. These class 2 serial data circuits are bussed together via two splice packs and a data link connector (DLC):
- SP205 - Located behind the I/P near the headlamp switch connector.
- SP306 - Located in the body harness near the rear of the right rear seat under the carpet.
- DLC - Connects the scan tool to the class 2 serial data circuits.
Refer to DATA LINK COMMUNICATIONS COMPONENT VIEWS .