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Test L: No Module/Network Communication - ISO 9141

NOTE: Depending on module configuration, with all modules connected and with ignition switch in RUN position or with engine running 2-3 volts may be present at Data Link Connector (DLC) terminal No. 7 (Light Blue/White wire). This is the International Standards Organization (ISO) 9141 diagnostic communications network circuit.
NOTE: If repairs to a module communication network circuit is required, see REPAIRING BUS WIRING  . If module replacement is necessary, see PROGRAMMING  and REMOVAL & INSTALLATION  .
  1. Turn ignition switch to OFF position. Inspect Data Link Connector (DLC) terminal No. 7 for damage. If DLC is okay, go to next step. If DLC is damaged, repair as necessary.
  2. Turn ignition switch to OFF position. Deactivate air bag system. See appropriate AIR BAG RESTRAINT SYSTEMS article. Disconnect Restraint Control Module (RCM) 26-pin harness connector C231. Inspect connector for damage. Repair as necessary. Measure resistance of Light Blue/White wire between terminal No. 7 at DLC and terminal No. 5 at RCM harness connector C231. See Figure and Figure . If resistance is less than 5 ohms, go to next step. If resistance 5 ohms or more, repair open in Light Blue/White wire between RCM harness connector C231 and DLC.
  3. Turn ignition switch to ON position. Perform data link diagnostics. See DATA LINK DIAGNOSTIC TEST  under SELF-DIAGNOSTIC SYSTEM. If vehicle is only equipped with RCM, and NGS tester indicates SYSTEM PASSED, go to step  14 . If vehicle is equipped with Parking Aid Module (PAM), and NGS tester does not indicate SYSTEM PASSED, go to next step.
  4. Turn ignition switch to OFF position. Connect RCM harness connector C231. Disconnect PAM 26-pin harness connector C445. Measure resistance of Light Blue/White wire between terminal No. 7 at DLC and terminal No. 5 at PAM harness connector C445. See Figure and Figure . If resistance is less than 5 ohms, go to step  7 . If resistance is 5 ohms or more, go to next step.
  5. Disconnect in-line 16-pin harness connector C292. Inspect connector for damage. Repair as necessary. Measure resistance of Light Blue/White wire between terminal No. 7 at DLC and terminal No. 5 at in-line 16-pin harness connector C292. See Figure and Figure . If resistance is less than 5 ohms, go to next step. If resistance is 5 ohms or more, repair open in Light Blue/White wire between DLC and in-line 16-pin harness connector.
  6. Turn ignition switch to OFF position. Disconnect in-line 14-pin harness connector C432. Measure resistance of Light Blue/White wire between terminal No. 5 at PAM harness connector C445 and terminal No. 9 at female side of in-line harness connector C432. If resistance is less than 5 ohms, repair open in Light Blue/White wire between female half of in-line harness connector C292 and female half of in-line harness connector C432. If resistance is 5 ohms or more, repair open in Light Blue/White wire between PAM harness connector C445 and female half of in-line harness connector C432.
  7. Turn ignition switch to ON position. Perform data link diagnostics. See DATA LINK DIAGNOSTIC TEST  under SELF-DIAGNOSTICS. If NGS tester indicates SYSTEM PASSED, go to step  17 . If vehicle is equipped with RPSDM, and NGS tester does not indicate SYSTEM PASSED, go to next step.
  8. Turn ignition switch to OFF position. Connect PAM harness connector C445. Disconnect RPSDM 12-pin harness connector C352. Measure resistance of Light Blue/White wire between terminal No. 10 at RPSDM harness connector C352 and terminal No. 7 at DLC. See Figure and Figure . If resistance is less than 5 ohms, go to step  10 . If resistance is 5 ohms or more, go to next step.
  9. Disconnect in-line 16-pin harness connector C292. Inspect connector for damage. Repair as necessary. Measure resistance of Light Blue/White wire between terminal No. 7 at DLC and terminal No. 5 at in-line 16-pin harness connector C292. See Figure and Figure . If resistance is less than 5 ohms, repair open in Light Blue/White wire between RPSDM harness connector C352 and in-line 16-pin harness connector C292. If resistance is 5 ohms or more, repair open in Light Blue/White wire between DLC and in-line 16-pin harness connector C292.
  10. Turn ignition switch to ON position. Perform data link diagnostics. See DATA LINK DIAGNOSTIC TEST  under SELF-DIAGNOSTIC SYSTEM. If NGS tester indicates, SYSTEM PASSED, go to step  15 . If vehicle is equipped with LPSDM, and NGS tester does not indicate SYSTEM PASSED, go to next step.
  11. Turn ignition switch to OFF position. Connect RPSDM harness connector C352. Disconnect LPSDM harness connector C355. Measure resistance of Light Blue/White wire between terminal No. 7 at DLC and terminal No. 10 at LPSDM harness connector C355. If resistance is less than 5 ohms, go to step  13 . If resistance is 5 ohms or more, go to next step.
  12. Disconnect in-line 16-pin harness connector C292. Measure resistance of Light Blue/White wire between terminal No. 7 at DLC and terminal No. 5 at in-line 16-pin harness connector C292. If resistance is less than 5 ohms, repair open in Light Blue/White wire between LPSDM harness connector C355 and in-line 16-pin harness connector C292. If resistance is 5 ohms or more, repair open in Light Blue/White wire between DLC and in-line 16-pin harness connector C292.
  13. Turn ignition switch to ON position. Perform data link diagnostics. See DATA LINK DIAGNOSTIC TEST  under SELF-DIAGNOSTIC SYSTEM. If NGS tester indicates, SYSTEM PASSED, go to step  16 . If NGS tester does not indicate SYSTEM PASSED, system is operating correctly at this time.
  14. Disconnect all RCM harness connectors. Inspect for corrosion, or pushed out pins. Connect all RCM harness connectors, ensuring connections are seated properly. Operate system. If concern is still present, replace RCM. Perform data link diagnostics. See DATA LINK DIAGNOSTIC TEST  under SELF-DIAGNOSTIC SYSTEM. If concern is not present, system is operating correctly at this time. Concern may have been caused by a loose or corroded connector.
  15. Disconnect all RPSDM harness connectors. Inspect for corrosion, or pushed out pins. Connect all RPSDM harness connectors, ensuring connections are seated properly. Operate system. If concern is still present, replace RPSDM. Perform data link diagnostics. See DATA LINK DIAGNOSTIC TEST  under SELF-DIAGNOSTIC SYSTEM. If concern is not present, system is operating correctly at this time. Concern may have been caused by a loose or corroded connector.
  16. Disconnect all LPSDM harness connectors. Inspect for corrosion, or pushed out pins. Connect all LPSDM harness connectors, ensuring connections are seated properly. Operate system. If concern is still present, LPSDM. Perform data link diagnostics. See DATA LINK DIAGNOSTIC TEST  under SELF-DIAGNOSTIC SYSTEM. If concern is not present, system is operating correctly at this time. Concern may have been caused by a loose or corroded connector.
  17. Disconnect all PAM harness connectors. Inspect for corrosion, or pushed out pins. Connect all PAM harness connectors, ensuring connections are seated properly. Operate system. If concern is still present, replace PAM. Perform data link diagnostics. See DATA LINK DIAGNOSTIC TEST  under SELF-DIAGNOSTIC SYSTEM. If concern is not present, system is operating correctly at this time. Concern may have been caused by a loose or corroded connector.
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