DTC U1300, U1301, Or U1305: Class 2 Serial Data Circuit Low: Description
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Serial data line is used to communicate information and commands between modules. When a module receives a message for a critical operating parameter (Node Alive message), a module records ID number of module which sent message for State Of Health (SOH) monitoring. Once an ID number is learned by a module, it will monitor for that module's Node Alive message. Each module on serial data line is required to send a Node Alive message every 2 seconds. When no message is detected from a learned ID number for 3 seconds, U1300 is set.