Test D: The Lighting Control Module (LCM) Does Not Respond To The Diagnostic Tool

PINPOINT TEST D: THE LIGHTING CONTROL MODULE (LCM) DOES NOT RESPOND TO THE DIAGNOSTIC TOOL

D1-D2:

D2-D3:

Normal Operation
The LCM communicates with the diagnostic tool through the standard corporate protocol (SCP) communications network, circuits 914 (TN/OG) and 915 (PK/LB). Check the SCP circuits 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 circuit in the SCP network, damage to the DLC C251, or damage to the LCM C2145a.

Possible Causes
- SCP data plus circuit 914 (TN/OG) open
- SCP data minus circuit 915 (PK/LB) open
- LCM C2145a
- LCM