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Test B: Scan Tool Does Not Communicate With Class 2 Device: Testing

  1. Connect scan tool to Data Link Connector (DLC). DLC is located below left side of instrument panel. If scan tool powers up, go to next step. If scan tool does not power up, perform TEST A: SCAN TOOL DOES NOT POWER UP .
  2. Turn ignition switch to RUN position. Attempt to communicate with each modules on class 2 serial data circuit. If scan tool communicates with any module, go to next step. If scan tool does not communicate with any module, go to step  5.
  3. Using scan tool, select DISPLAY DTCs function for each module. Record all DTCs, status of DTCs and module which set DTC. If DTCs U1000-U1255 are displayed, go to next step. If DTCs U1000-U1255 are not displayed, see DIAGNOSTIC AIDS .
  4. If DTC U1000 is displayed, perform DTC U1000 & U1255: CLASS 2 COMMUNICATION MALFUNCTION  under DIAGNOSTIC TESTS. If DTC U1001-U1254 is displayed, perform DTC U1001-U1254: LOSS OF XXX COMMUNICATIONS  under DIAGNOSTIC TESTS.
  5. Turn ignition switch to OFF position. Disconnect scan tool from DLC. Inspect DLC connector terminals No. 2 and 5 for poor connections. See Figure. If poor connections are not found, go to next step. If poor connections are found, repair as necessary then perform appropriate diagnostic system check. See DIAGNOSTIC SYSTEM CHECK  table under SELF-DIAGNOSTIC SYSTEM.
  6. Inspect Black/White wire for an open between ground and DLC connector terminal No. 5. If an open is not found, go to next step. If an open is found, repair as necessary then perform appropriate diagnostic system check. See DIAGNOSTIC SYSTEM CHECK  table under SELF-DIAGNOSTIC SYSTEM.
  7. Disconnect splice pack 12-pin connector. Splice pack is located behind left side of instrument panel, near DLC. See Figure. Inspect splice pack connector for poor or corroded connections. If poor or corroded connections are not found, go to next step. If poor or corroded connections are found, repair as necessary then perform appropriate diagnostic system check. See DIAGNOSTIC SYSTEM CHECK  table under SELF-DIAGNOSTIC SYSTEM.
  8. Inspect Purple wire for an open or short between DLC connector terminal No. 2 and splice pack connector terminal "G". See Figure and Figure . If an open or short is not found, go to next step. If an open or short is found, repair as necessary then perform appropriate diagnostic system check. See DIAGNOSTIC SYSTEM CHECK  table under SELF-DIAGNOSTIC SYSTEM.
  9. Connect a 3-amp fused jumper wire to splice pack connector terminal "G" (Purple wire). See Figure. Connect other end of jumper wire to splice pack connector terminal "C" (Dark Green wire). Turn ignition switch to RUN position. Using scan tool, attempt to communicate with Powertrain Control Module (PCM). If PCM does not communicate with scan tool, remove jumper wires and go to next step. If PCM communicates with scan tool, go to step  11.
    10. NOTE: Ignition switch must be in RUN position to test for short to voltage.
  10. Turn ignition switch to OFF position. Disconnect PCM 80-pin harness connector. PCM is located in right side of engine compartment, near rear of wheelwell. Inspect Dark Green wire for a short to ground or short to voltage between PCM harness connector terminal No. 59 (3.8L) or No. 58 (5.7L) and splice pack connector terminal "C". See Figure and Figure . If short to ground or short to voltage is not found, go to step  17. If short to ground or short to voltage is found, repair as necessary then go to step  19.
  11. Remove jumper wire from splice pack connector terminal "C", and connect to terminal "E". See Figure. Turn ignition switch to RUN position. Attempt to communicate with Sensing Diagnostic Module (SDM). If scan tool does not communicate with SDM, remove jumper wires and go to next step. If scan tool communicates with SDM, go to step  13.
    12. NOTE: Ignition switch must be in RUN position to test for short to voltage.
  12. Turn ignition switch to OFF position. Disconnect SDM 18-pin harness connector. SDM is located below center console, near parking brake handle. See Figure. Inspect Dark Blue wire for a short to ground or short to voltage between SDM harness connector terminal A4 and splice pack connector terminal "E". See Figure and Figure . If a short to ground or short to voltage is not found, go to step  17. If a short to ground or short to voltage is found, repair as necessary then go to step  19.
  13. Disconnect jumper wire from splice pack connector terminal "E", and connect to terminal "J". See Figure. Turn ignition switch to RUN position. Attempt to communicate with Electronic Brake Control Module (EBCM). If scan tool does not communicate with EBCM, remove jumper wires and go to next step. If scan tool communicates with EBCM, go to step  15.
    14. NOTE: Ignition switch must be in RUN position to test for short to voltage.
  14. Turn ignition switch to OFF position. Disconnect EBCM 30-pin harness connector. EBCM is located top of left front frame rail. See Figure. Inspect Light Blue wire for a short to ground or short to voltage between EBCM harness connector terminal No. 25 and splice pack connector terminal "J". See Figure and Figure . If a short to ground or short to voltage is not found, go to step  17. If a short to ground or short to voltage is found, repair as necessary then go to step  19.
  15. Remove jumper wire from splice pack connector terminal "J", and connect to terminal "L". See Figure. Turn ignition switch to RUN position. Attempt to communicate with Instrument Panel Cluster (IPC). If scan tool does not communicate with IPC, remove jumper wires and go to next step. If scan tool communicates with IPC, go to step  19.
    16. NOTE: Ignition switch must be in RUN position to test for short to voltage.
  16. Turn ignition switch to OFF position. Disconnect IPC 34-pin harness connector. IPC is located behind instrument cluster. See Figure. Inspect Gray wire for a short to ground or short to voltage between IPC harness connector terminal B6 and splice pack connector terminal "L". See Figure and Figure . If a short to ground or short to voltage is not found, go to next step. If a short to ground or short to voltage is found, repair as necessary then go to step  19.
  17. Inspect class 2 serial data circuit for module that is not communicating for poor connections. If poor connection is not found, go to next step. If poor connection is found, repair as necessary then go to step  19.
  18. Replace module that is not communicating. Program module, if necessary. See PROGRAMMING . After replacement, go to next step.
  19. Connect all modules and connectors, if disconnected. Connect scan tool to DLC. DLC is located left side of instrument panel, to right of steering column. Turn ignition switch to RUN position. Wait 10 seconds for scan tool to complete power up reset. Turn scan tool if power reset is necessary. Using scan tool, select DISPLAY DTCs function for each module. Record all displayed DTCs and status. If any DTCs which begin with "U" and a current status are not recorded, go to next step. If any DTCs which begin with "U" and a current status are recorded, go to step  21.
  20. If any DTCs which do not begin with "U" are recorded, go to next step. If any DTCs are recorded, go to step  23.
  21. Perform appropriate test in accordance with DTC retrieved. See DIAGNOSTIC TROUBLE CODE DEFINITIONS  table under SELF-DIAGNOSTIC SYSTEM. After repair is completed, go to next step.
  22. If all DTCs have been diagnosed, go to next step. If all DTCs have not been diagnosed, go to step  21.
  23. Using scan tool, clear DTCs. After clearing DTCs, system should be operating correctly at this time.
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