Operation CHARM: Car repair manuals for everyone.
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Link: lemon-manuals.la or lemon-manuals.org.ua

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Test H: No Medium Speed Controller Area Network (CAN) Communication

PINPOINT TEST H: NO MEDIUM SPEED CONTROLLER AREA NETWORK (CAN) COMMUNICATION


H1-H2:






H2-H4:






H4-H6:






H6-H9:






H9-H11:






H11-H13:






H13-H16:






H17:






Normal Operation
The medium speed CAN has an unshielded twisted pair cable, circuits 1847 (WH/OG) and 1848 (PK/OG). The audio unit, the instrument cluster, and the smart junction box (SJB) are all on the medium speed CAN. The total resistance values from the data link connector (DLC) C251 must not be more than 5 ohms. If the resistance is more than 5 ohms there is an open in one of the medium speed CAN circuits, damage to the DLC C251, damage to one of the communications network module connectors, or damage to an in-line connector.

Possible Causes
- medium speed CAN circuit 1847 (WH/OG) short to ground, short to voltage, or open
- medium speed CAN circuit 1848 (PK/OG) short to ground, short to voltage, or open
- DLC C251
- audio unit C290a
- instrument cluster C220
- SJB C2280b
- audio unit
- instrument cluster
- SJB