Test H: The Lighting Control Module (LCM) Does Not Respond To The Diagnostic Tool
PINPOINT TEST H: THE LIGHTING CONTROL MODULE (LCM) DOES NOT RESPOND TO THE DIAGNOSTIC TOOLH1-H2:
H2-H3:
Normal Operation
The LCM communicates with the diagnostic tool through the standard corporate protocol (SCP) communication network, circuits 914 (TN/OG) and 915 (PK/LB). Check the SCP circuits 914 (TN/OG) and 915 (PK/LB) between the LCM C2145a and the data link connector (DLC) C251. The total resistance values must not be more than 5 ohms. If the resistance is more than 5 ohms, there is an open in the SCP network circuits, damage to the DLC C251, the LCM C2145a, or a problem in the in-line connectors.
Possible Causes
- SCP data plus circuit 914 (TN/OG) open
- SCP data minus circuit 915 (PK/LB) open
- LCM C2145a
- LCM