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

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


D1-D2:






D2-D3:






D4:






Normal Operation
The LCM communicates with the scan tool through the standard corporate protocol (SCP) communication network. Circuits 914 (TN/OG) (SCP +) and 915 (PK/LB) (SCP-) provide the network connection to the LCM. The LCM shares the SCP network with the driver door module (DDM) (if equipped), the electronic automatic temperature control (EATC) module (if equipped) and the overhead console (if equipped). Voltage for the LCM is provided by circuit 221 (OG/WH). Circuit 676 (PK/OG) provides ground.

Possible Causes
- Fuse
- Circuit 221 (OG/WH) open
- Circuit 676 (PK/OG) open
- Circuit 914 (TN/OG) open (SCP +)
- Circuit 915 (PK/LB) open (SCP -)
- LCM