Operation CHARM: Car repair manuals for everyone.
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Our trusted friends have launched a new website named LEMON, which has newer manuals. It also contains all the CHARM manuals.

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Link: lemon-manuals.la or lemon-manuals.org.ua

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Test L

PINPOINT TEST L: NO STANDARD CORPORATE PROTOCOL (SCP) NETWORK COMMUNICATION


Test L1-L2:






Test L2-L3:






Test L4-L10:






Test L11-L12:






Test L13-L15:






Test L16-L21:






Normal Operation
The SCP network provides data transfer between modules within the vehicle through a single pair of twisted wires. The data link connector (DLC) provides diagnostic tools access to vital SCP network and module information through circuits 4-EG7 (GY) and 5-EG7 (LB). Degraded SCP performance occurs if one bus line is open, shorted to ground or voltage, or if one but not all termination resistors are lost. To accurately diagnose the SCP communication network, the data link diagnostics test must be run with the module in question disconnected.

Possible Causes
- SCP network circuits
- DLC C251
- anti-lock brake system (ABS) module
- audio control module (ACM)
- dual automatic temperature control (DATC) module
- front electronic module (FEM)
- instrument cluster
- powertrain control module (PCM)
- rear electronic module (REM)
- remote keyless entry (RKE) module