DTC U1300: Class 2 Data Link Low In Data Link Communication

Modules connected to the class 2 serial data circuit monitor for serial data communications during normal vehicle operation. Operating information and commands are exchanged among the modules. In addition to this, Node Alive (State of Health) messages are transmitted by each module on the class 2 serial data circuit about once every 2 seconds. When module detects no messages and a low voltage on the class 2 serial data circuit for about 10 seconds, DTC U1300 is set and the setting of all other class 2 serial communication DTCs is inhibited.

DTC will set when no valid messages are detected on the class 2 serial data circuit, voltage level detected on the class 2 serial data circuit is low and these are met for more than 10 seconds.