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DTC U1255: Class 2 Initialization Error: Testing

  1. Perform DATA LINK COMMUNICATIONS DIAGNOSTIC SYSTEM CHECK  under SYSTEM TESTS. Go to next step.
  2. Attempt to establish communication with all modules using scan tool. If communication cannot be established, diagnose and repair problem in appropriate module. If communication can be established, go to next step.
  3. Repair intermittent connections in Purple wire. See appropriate wiring diagram in DATA LINK CONNECTORS article in WIRING DIAGRAMS. After repairs, go to next step.
  4. Turn ignition off. Reconnect all disconnected components and connectors. Turn ignition on and use scan tool to clear DTCs. Go to DATA LINK COMMUNICATIONS DIAGNOSTIC SYSTEM CHECK  under SYSTEM TESTS.