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Test H: Scan Tool Does Not Communicate With Class 2 Device

  1. Perform diagnostic system check. See DIAGNOSTIC SYSTEM CHECK  under DIAGNOSIS & TESTING. After performing diagnostic system check, go to next step.
  2. Turn ignition on, with engine off. Using scan tool, attempt to communicate with each module on the class 2 serial data circuit. If scan tool communicates with any module on the class 2 serial data circuit, go to next step. If scan tool, does not communicate with any module on the class 2 serial data circuit, go to step  5 .
  3. Using scan tool, select display DTCs function for each module and record all of the displayed DTCs and status, and module which set DTC. If DTCs recorded are in the range of DTC U1000 to U1255, go to next step. If DTCs recorded are not in the U1000 or U1255 range, problem is intermittent.
  4. If DTC U1000 or U1255 is the only DTC displayed. Diagnose affected DTCs. See appropriate BODY CONTROL MODULES article in ACCESSORIES & EQUIPMENT. If other than DTC U1000 or U1255 is set, diagnose affected "U" series DTCs. See apropriate BODY CONTROL MODULES article in ACCESSORIES & EQUIPMENT.
  5. Turn off ignition. Disconnect scan tool from DLC. Check for poor connections or terminal tension at DLC terminals No. 2 and 5. See WIRING DIAGRAMS  . Repair as necessary. If connections or terminal tension is okay, go to next step.
  6. Check for open in DLC terminal No. 5 (ground circuit). Repair as necessary. If circuit is okay, go to next step.
  7. Disconnect splice pack connector SP205. See WIRING DIAGRAMS  . Check for poor connections/terminal tension at splice pack. Repair as necessary. If connections or tension is okay, go to next step.
  8. Check for open or a short between DLC terminal No. 2 and splice pack SP205 terminal "A". Repair as necessary. If circuit is okay, go to next step.
  9. Using Terminal Adapter (J-35616-A), connect a jumper wire to terminal "A" of splice pack SP205. Connect other end of jumper wire (with correct terminal adapter) to terminal "B" of splice pack SP205. Turn ignition on, with engine off. Using scan tool, attempt to communicate with PCM. If scan tool communicates with PCM, go to step  11 . If scan tool does not communicate with PCM, go to next step.
  10. Turn ignition off. Disconnect PCM harness connector. Check class 2 serial data circuit between splice pack SP205 and PCM for short to ground or short to voltage. Repair as necessary. After repairs, go to step  25 . If circuit is okay, go to step  23 .
  11. Disconnect jumper wire from terminal "B" of splice pack SP205. Connect jumper wire to terminal "F" of splice pack SP205. Turn ignition on, with engine off. Using scan tool, attempt to communicate with Sensing and Diagnostic Module (SDM). If scan tool communicates with SDM, go to step  13 . If scan tool, does not communicate with SDM, go to next step.
  12. Turn ignition off. Disconnect SDM harness connector. Check class 2 serial data circuit between splice pack SP205 and SDM for short to ground or short to voltage. Turn ignition on, with engine off when testing for short to voltage. Repair as necessary. After repairs, go to step  25 . If circuit is okay, go to step  23 .
  13. Disconnect jumper wire from terminal "F" of splice pack SP205. Connect jumper wire to terminal "E" of splice pack SP205. Turn ignition on, with engine off. Using scan tool, attempt to communicate with EBCM. If scan tool communicates with EBCM, go to step  15 . If scan tool does not communicate with EBCM, go to next step.
  14. Turn ignition off. Disconnect EBCM harness connector. Check the class 2 serial data circuit between splice pack SP205 and EBCM for short to ground or short to voltage. Turn ignition on when testing for short to voltage. Repair as necessary. After repairs, go to step  25 . If circuit is okay, go to step  23 .
  15. Disconnect jumper wire from terminal "E" of splice pack SP205. Connect jumper wire to terminal "G" of splice pack SP205. Turn ignition on, with engine off. Using scan tool, attempt to communicate with instrument cluster. If scan tool communicates with instrument cluster, go to step  17 . If scan tool does not communicate with instrument cluster, go to next step.
  16. Turn ignition off. Disconnect instrument cluster harness connector. Check the class 2 serial data circuit between splice pack SP205 and instrument cluster for short to ground or short to voltage. Turn ignition on when testing for short to voltage. Repair as necessary. After repairs, go to step  25 . If circuit is okay, go to step  23 .
  17. Disconnect jumper wire from terminal "G" of splice pack SP205. Connect jumper wire to terminal "M" of splice pack SP205. Turn ignition on, with engine off. Using scan tool, attempt to communicate with PassKey III module. If scan tool communicates with PassKey III module, go to step  19 . If scan tool does not communicate with Pass Key III module, go to next step.
  18. Turn ignition off. Disconnect PassKey III module harness connector. Check class 2 serial data circuit between splice pack SP205 and PassKey III module for short to ground or short to voltage. Turn ignition on when testing for short to voltage. Repair as necessary. After repairs, go to step  25 . If circuit is okay, go to step  23 .
  19. Disconnect jumper wire from terminal "M" of splice pack SP205. Connect jumper wire to terminal "K" of splice pack SP205. Turn ignition on, with engine off. Using scan tool, attempt to communicate with Driver Information Center (DIC) display. If scan tool communicates with DIC, go to next step. If scan tool does not communicate with DIC, go to step  21 .
  20. Disconnect jumper wire from terminal "K" of splice pack SP205. Connect jumper wire to terminal "D" of splice pack SP205. Turn ignition on, with engine off. Using scan tool, attempt to communicate with radio. If scan tool communicates with radio, go to step  25 . If scan tool does not communicate with radio, go to step  22 .
  21. Turn ignition off. Disconnect DIC. Check class 2 serial data circuit between splice pack SP205 and DIC for short to ground or short to voltage. Turn ignition on, with engine off when testing for short to voltage. Repair as necessary. After repairs, go to step  25 . If circuit is okay, go to step  23 .
  22. Turn ignition off. Disconnect radio harness connector. Check class 2 serial data circuit between splice pack SP205 and radio for short to ground or short to voltage. Turn ignition off, engine off when testing for short to voltage. Repair as necessary. After repairs, go to step  25 . If circuit is okay, go to next step.
  23. Check for poor connections/terminal tension at class 2 serial data circuit of module that is not communicating. Repair as necessary. After repairs, go to step  25 . If circuit is okay, go to next step.
  24. Replace module which is not communicating. After replacing module, go to next step.
  25. Reconnect all of disconnected modules and connectors. Install scan tool. Turn ignition on, with engine off. Wait 10 seconds. Scan tool may require a power up reset before communication will occur due to a short on class 2 serial data circuit. Turn off or disconnect scan tool prior to performing this test. Select display DTCs function for each module. Record all of displayed DTCs and DTC status. If any DTCs recorded begins with a "U" and with a current status, go to step  27 . If DTCs recorded are not "U" series DTCs, go to next step.
  26. Diagnose affected DTCs as directed by diagnostic procedures. After repairs, go to next step.
  27. Using scan tool, check and record DTCs. If any DTCs are present, diagnose affected DTCs. After diagnosing all DTCs, clear DTCs using scan tool.
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