DTC P2637 Hyundai

Description

Modules connected to the Class 2 circuit monitor for serial data communications during normal vehicle operation. Operating information and commands are exchanged among the modules. When a module receives a message for a critical operating parameter, the module records the identification number of the module that sent the message. These Node Alive messages are used for State of Health monitoring. A critical operating parameter is one which, when not received, requires that the module use a default value for that parameter. When a module does not associate an identification number with at least one critical parameter within 5 seconds of starting data communication, DTC U1000 or U1255 is set. When more than one critical parameter does not have an identification number associated with it, the code will only set once.