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DTC UXXX: Lost Communication With XXX: Testing

  1. Check for short to ground in positive battery voltage circuits and ignition voltage circuit(s) of module(s) not communicating. Repair as necessary. After repair, go to step  10 . If battery and ignition voltage circuit(s) are okay, go to next step.
  2. Turn ignition switch to OFF position. Check for open or high resistance in ground circuit(s) of module(s) not communicating. Repair as necessary. After repair, go to step  10 . If ground circuit(s) are okay, go to next step.
  3. Disconnect splice pack SP205. Check for poor terminal contact at splice pack SP205 harness connector. Repair as necessary. After repair, go to step  7 . If terminal contact is okay, go to next step.
  4. Check class 2 serial data circuit for open between splice pack connector SP205 and module that is not communicating. See appropriate wiring diagram in DATA LINK CONNECTORS article in WIRING DIAGRAMS. Repair as necessary. After repair, go to step  7 . If class 2 serial data circuits are okay, go to next step.
  5. Check for poor terminal connections at battery voltage, ignition voltage, class 2 serial data and ground circuits of module(s) that are not communicating. Repair terminal connections as necessary. See appropriate wiring diagram in DATA LINK CONNECTORS article in WIRING DIAGRAMS. If terminal connections are okay, go to next step.
  6. Replace module that is not communicating. Go to appropriate system for replacement procedures. After repair, go to step  10 .
  7. Connect scan tool to DLC. Turn ignition switch to RUN position. Select DISPLAY DTCs function for module that was communicating. If scan tool displays any DTCs other than communication DTCs exist (DTCs beginning with a "U"), go to appropriate system diagnostic system check starting point for related system. If no DTCs other than communication DTCs, go to next step.
  8. Clear all DTCs using scan tool, then go to next step.
  9. Select DISPLAY DTCs function for module(s) which had lost communication with XXX set. If any DTCs that do not begin with "U" exist, go to appropriate system diagnostic system check starting point for related system. If no DTCs exist, go to next step.
  10. Select DISPLAY DTCs function for module that stored lost communication with xxx set. If any DTCs other than communication DTCs exist, go to appropriate system diagnostic system check starting point for related system. If no other DTCs exist that are not communication DTCs, go to next step.
  11. Using scan tool, clear DTCs. Repair any DTCs from all modules as necessary.
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