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SCP Network Failure Modes

NOTE: When a network failure is indicated, use a DVOM for diagnosis. A scan tool is only capable of testing network signals.

An open circuit in a SCP high (+) or SCP low (-) wire will not stop communication. Data will only be transferred with good circuits and chassis grounds. If both wires are open, some data will be lost and signal communication will stop at the open circuit. Communication will continue between modules on same side of open. Different circuit conditions will give different network conditions. See NETWORK COMMUNICATION FAILURE CONDITIONS  table.

NETWORK COMMUNICATION FAILURE CONDITIONS

Wire Condition Communication
SCP High (+) Open Yes, If SCP Low (-) Is Functioning
SCP High (+) Short To Ground Yes, If SCP Low (-) Is Functioning
SCP High (+) Short To Battery No
SCP High (+) Short To SCP Low (-) No
SCP Low (-) Open Yes, If SCP High (+) Is Functioning
SCP Low (-) Short To Ground No
SCP Low (-) Short To Battery Yes, If SCP High (+) Is Functioning
SCP Low (-) Short To SCP High (+) No