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DTC U1300: Class 2 Circuit (Short To Ground): Testing

  1. Perform Data Link Connector (DLC) diagnostic system check. Go to DLC DIAGNOSTIC SYSTEM CHECK  under SYSTEM TESTS. After DLC diagnostic system check is performed, go to next step.
  2. Turn ignition on. Using scan tool, clear DTCs. Check for DTCs. If DTC U1300 is set, go to next step. If DTC U1300 is not set, go to step  4 .
  3. Class 2 serial data link circuit is okay. Module that is setting DTC has internal malfunction. Go to appropriate diagnostic and repair procedures. After repairs, go to step  5 .
  4. System is operating properly at this time. See DIAGNOSTIC AIDS  . After any repairs are made, go to next step.
  5. Turn ignition off. Reinstall all components and connectors. Turn ignition on. Using scan tool, clear DTCs. Check for DTCs. If any DTCs are current, perform BCM DIAGNOSTIC SYSTEM CHECK  under SYSTEM TESTS. If no DTCs are current, system is operating properly.
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