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Scan Tool Does Not Communicate With Class 2 Data Line: Testing

  1. Perform DATA LINK CONNECTOR (DLC) DIAGNOSTIC SYSTEM CHECK  . Go to next step.
  2. If scan tool is properly programmed to communicate with malfunctioning vehicle, go to next step. If scan tool is not programmed properly, go to step  28 .
  3. Connect scan tool to known-good vehicle and perform DATA LINK CONNECTOR (DLC) DIAGNOSTIC SYSTEM CHECK  . If scan tool communicates, go to next step. If scan tool does not communicate, go to step  28 .
  4. Turn ignition off on malfunctioning vehicle. Disconnect splice pack SP205. SP204 is located below instrument panel on right side of steering column. Use DVOM to measure resistance between ground and DLC terminal No. 2 (Purple wire). See appropriate wiring diagram in DATA LINK CONNECTORS article in WIRING DIAGRAMS. If reading is infinite, go to next step. If any resistance is indicated, go to step  29 .
  5. Use DVOM to measure voltage between ground and DLC terminal No. 2 (Purple wire). If reading is less than 2 volts, go to next step. If reading is greater than 2 volts, go to step  30 .
  6. Use DVOM to measure resistance between DLC terminal No. 2 and SP205 terminal "A" (Purple wire). See WIRING DIAGRAMS  . If reading is less than 2 ohms, go to next step. If reading is greater than 2 ohms, go to step  31 .
  7. Turn ignition off. Disconnect negative battery terminal. Reconnect SP205. Use DVOM to backprobe and measure resistance between SP205 connector terminal "A" (Purple wire) and following SP205 terminals:
    • "B" (Dark Green wire)
    • "E" (Light Blue wire)
    • "F" (Dark Blue wire)
    • "G" (Gray wire)
    • "M" (Light Green wire)

    If reading is less than 2 ohms at one or more terminals, go to next step. If reading is greater than 2 ohms at one or more terminals, go to step  32 .

  8. Disconnect SP205. Disconnect PCM connector C1. Use DVOM to measure resistance between SP205 connector terminal "B" (Dark Green wire) and ground. If reading is infinite, go to next step. If any resistance is indicated, go to step  33 .
  9. Reconnect negative battery terminal. Turn ignition on. Use DVOM to measure voltage between SP205 connector terminal "B" (Dark Green wire) and ground. If reading is less than 2 volts, go to next step. If reading is greater than 2 volts, go to step  34 .
  10. Use DVOM to measure resistance between SP205 terminal "B" and PCM connector C1 terminal No. 58 (Dark Green wire). See Figure . If reading is less than 2 ohms, go to next step. If reading is greater than 2 ohms, go to step  35 .
  11. Turn ignition off. Disconnect Electronic Brake Traction Control Module (EBTCM) connector. Use DVOM to measure resistance between SP205 connector terminal "E" (Light Blue wire) and ground. If reading is infinite, go to next step. If any resistance is indicated, go to step  36 .
  12. Use DVOM to measure voltage between SP205 connector terminal "E" (Light Blue wire) and ground. If reading is less than 2 volts, go to next step. If reading is greater than 2 volts, go to step  37 .
  13. Use DVOM to measure resistance between SP205 terminal "E" and EBTCM connector terminal B7 (Light Blue wire). If reading is less than 2 ohms, go to next step. If reading is greater than 2 ohms, go to step  38 .
  14. Turn ignition off. Disconnect Instrument Panel Cluster (IPC) connector. Use DVOM to measure resistance between SP205 connector terminal "G" (Gray wire) and ground. If reading is infinite, go to next step. If any resistance is indicated, go to step  39 .
  15. Use DVOM to measure voltage between SP205 connector terminal "G" (Gray wire) and ground. If reading is less than 2 volts, go to next step. If reading is greater than 2 volts, go to step  40 .
  16. Use DVOM to measure resistance between SP205 terminal "G" and IPC connector terminal B7 (Gray wire). If reading is less than 2 ohms, go to next step. If reading is greater than 2 ohms, go to step  41 .
  17. If vehicle is not equipped with automatic climate control (CJ2), go to step  20 . If vehicle is equipped with automatic climate control, turn ignition off and disconnect A/C-heater control panel connector. Use DVOM to measure resistance between SP205 connector terminal "L" (White wire) and ground. If reading is infinite, go to next step. If any resistance is indicated, go to step  42 .
  18. Use DVOM to measure voltage between SP205 connector terminal "L" (White wire) and ground. If reading is less than 2 volts, go to next step. If reading is greater than 2 volts, go to step  43 .
  19. Use DVOM to measure resistance between SP205 terminal "L" and A/C-heater control panel connector terminal D12 (White wire). If reading is less than 2 ohms, go to next step. If reading is greater than 2 ohms, go to step  44 .
  20. Turn ignition off. Disconnect Body Control Module (BCM) connector C2. Use DVOM to measure resistance between SP205 connector terminal "M" (Light Green wire) and ground. If reading is infinite, go to next step. If any resistance is indicated, go to step  45 .
  21. Use DVOM to measure voltage between SP205 connector terminal "M" (Light Green wire) and ground. If reading is less than 2 volts, go to next step. If reading is greater than 2 volts, go to step  46 .
  22. Use DVOM to measure resistance between SP205 terminal "M" and BCM connector C2 terminal B5 (Light Green wire). If reading is less than 2 ohms, go to next step. If reading is greater than 2 ohms, go to step  47 .
  23. Turn ignition off. Reconnect PCM connector C1. Leave other modules disconnected. Reconnect SP205. Turn ignition on. Use scan tool to establish communications with PCM. If scan tool communicates with PCM, go to next step. If scan tool does not communicate with PCM, go to SELF-DIAGNOSTICS - GASOLINE EXCEPT METRO, PRIZM & TRACKER article in ENGINE PERFORMANCE.
  24. Turn ignition off. Reconnect EBTCM connector. Leave other modules disconnected. Turn ignition on. Use scan tool to establish communications with EBTCM. If scan tool communicates with EBTCM, go to next step. If scan tool does not communicate with EBTCM, go to appropriate ANTI-LOCK BRAKES article in BRAKES.
  25. Turn ignition off. Reconnect IPC connector. Leave other modules disconnected. Turn ignition on. Use scan tool to establish communications with IPC. If scan tool communicates with IPC, go to next step. If scan tool does not communicate with IPC, go to appropriate ANALOG INSTRUMENT PANELS article.
  26. If vehicle is not equipped with automatic climate control (CJ2), go to step  27 . If vehicle is equipped with automatic climate control, turn ignition off. Reconnect A/C-heater control panel connector. Leave other modules disconnected. Turn ignition on. Use scan tool to establish communications with HVAC. If scan tool communicates with HVAC, go to next step. If scan tool does not communicate with HVAC, go to appropriate AUTOMATIC A/C-HEATER SYSTEMS article in AIR CONDITIONING & HEATING..
  27. Turn ignition off. Reconnect BCM connector. Leave other modules disconnected. Turn ignition on. Use scan tool to establish communications with BCM. If scan tool communicates with BCM, go to next step. If scan tool does not communicate with BCM, go to BCM DIAGNOSTIC SYSTEM CHECK  .
  28. Check scan tool manufactures instructions for correct operation of scan tool. Perform DATA LINK CONNECTOR (DLC) DIAGNOSTIC SYSTEM CHECK  .
  29. Repair short to ground in Purple wire to DLC terminal No. 2. After repairs, go to step  48 .
  30. Repair short to voltage in Purple wire to DLC terminal No. 2. After repairs, go to step  48 .
  31. Repair poor connection or open in Purple wire to DLC terminal No. 2. After repairs, go to step  48 .
  32. Replace SP205. After repairs, go to step  48 .
  33. Repair short to ground in Dark Green wire to PCM. After repairs, go to step  48 .
  34. Repair short to voltage in Dark Green wire to PCM. After repairs, go to step  48 .
  35. Repair poor connection or open in Dark Green wire to PCM. After repairs, go to step  48 .
  36. Repair short to ground in Light Blue wire to EBTCM. After repairs, go to step  48 .
  37. Repair short to voltage in Light Blue wire to EBTCM. After repairs, go to step  48 .
  38. Repair poor connection or open in Light Blue wire to EBTCM. After repairs, go to step  48 .
  39. Repair short to ground in Gray wire to IPC. After repairs, go to step  48 .
  40. Repair short to voltage in Gray wire to IPC. After repairs, go to step  48 .
  41. Repair poor connection or open in Gray wire to IPC. After repairs, go to step  48 .
  42. Repair short to ground in White wire to A/C-heater control panel. After repairs, go to step  48 .
  43. Repair short to voltage in White wire to A/C-heater control panel. After repairs, go to step  48 .
  44. Repair poor connection or open in White wire to A/C-heater control panel. After repairs, go to step  48 .
  45. Repair short to ground in Light Green wire to BCM. After repairs, go to step  48 .
  46. Repair short to voltage in Light Green wire to BCM. After repairs, go to step  48 .
  47. Repair poor connection or open in Light Green wire to BCM. After repairs, go to step  48 .
  48. Turn ignition off. Reinstall all disconnected components and connectors. Perform DATA LINK CONNECTOR (DLC) DIAGNOSTIC SYSTEM CHECK  .
  49. Turn ignition off. Disconnect Sensing and Diagnostic Module (SDM) connector for air bag system. Use DVOM to measure resistance between SP205 connector terminal "F" (Dark Blue wire) and ground. If reading is infinite, go to next step. If any resistance is indicated, go to step  52 .
  50. Use DVOM to measure voltage between SP205 connector terminal "F" (Dark Blue wire) and ground. If reading is less than 2 volts, go to next step. If reading is greater than 2 volts, go to step  53 .
  51. Use DVOM to measure resistance between SP205 terminal "F" and SDM connector terminal A5 (Dark Blue wire). If reading is less than 2 ohms, go to next step. If reading is greater than 2 ohms, go to step  54 .
  52. Repair short to ground in Dark Blue wire to SDM. After repairs, go to step  48 .
  53. Repair short to voltage in Dark Blue wire to SDM. After repairs, go to step  48 .
  54. Repair poor connection or open in Dark Blue wire to SDM. After repairs, go to step  48 .
  55. Check for poor connections, corroded or loose terminals at DLC or module connectors. Repair as necessary. Go to next step.
  56. Turn ignition off. Reconnect SDM connector. Use scan tool to establish communications with SDM. If scan tool communicates with SDM, go to DATA LINK CONNECTOR (DLC) DIAGNOSTIC SYSTEM CHECK  . If scan tool does not communicate with SDM, go to AIR BAG SERVICE & REPAIR MANUAL.
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