Cobalt L4-2.0L SC VIN P (2005)
Information Bus: Symptom Related Diagnostic Procedures
Scan Tool Does Not Communicate With Class 2 Device
SCAN TOOL DOES NOT COMMUNICATE WITH CLASS 2 DEVICE
CIRCUIT DESCRIPTION
The powertrain control module (PCM) is connected to the class 2 serial data circuit. The class 2 serial data circuit is used for diagnostic purposes only
in this vehicle. Connecting a scan tool to the data link connector (DLC) allows communication with the PCM for diagnostic purposes. DTCs may be
set due to this symptom and during this diagnostic procedure. Complete the diagnostic procedure in order to ensure all the DTCs are diagnosed and
cleared from memory.
DIAGNOSTIC AIDS
The PCM is the only module on the class 2 serial data buss on this vehicle. The most likely cause of the buss failure will be a short or open.
TEST DESCRIPTION
Steps 1-8
