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Test K: No Module/Network Communications - ISO 9141 Link

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.
  1. Inspect NGS tester connector for loose, damaged or corroded terminals. Pay particular attention to terminal No. 7. Repair connector as necessary and retest system for normal operation. If connector is okay, go to next step.
  2. Turn ignition off. Inspect Data Link Connector (DLC) for physical damage, bent terminals or corrosion. Pay particular attention to terminal No. 7 (Light Blue/White wire). Repair connector as necessary and retest system for normal operation. If connector is okay, go to next step.
  3. Ensure ignition is off. Disconnect GEM/CTM 26-pin connector C280 located behind center of instrument panel. See Figure. Measure resistance of Light Blue/White wire between terminal No. 25 at GEM/CTM 26-pin connector and terminal No. 7 at DLC. See Figure and Figure . If resistance is 5 ohms or more, repair open Light Blue/White wire between DLC and GEM/CTM connector. Retest system for normal operation. If resistance is less than 5 ohms, go to next step.
  4. If vehicle is equipped with a Remote Anti-Theft Personality (RAP) module, Parking Aid Module (PAM) or a Driver Seat Module (DSM), go to next step. If vehicle is not equipped with a RAP module, PAM or a DSM, go to step  6.
  5. Disconnect 84-pin in-line connector C212 located at left corner of instrument panel, near cowl panel grommet. See Figure. Turn ignition on. Measure voltage between terminals No. 7 (Light Blue/White wire) and No. 16 (Orange wire) at DLC. See Figure. Also, measure voltage between terminals No. 7 (Light Blue/White wire) and No. 4 (Black wire) at DLC. If any reading indicates voltage, go to next step. If both readings indicate zero volts, proceed as follows:
    • If vehicle is equipped with a combination of RAP module, PAM or DSM, go to step  11.
    • If vehicle is equipped with a RAP module only, go to step  18.
    • If vehicle is equipped with a PAM only, go to step  19.
    • If vehicle is equipped with a DSM only, go to step  20.
  6. Turn ignition off. Reconnect in-line connector C212. Disconnect 40-pin bulkhead connector C148 located at left rear of engine compartment, near brake master cylinder. See Figure. Turn ignition on. Measure voltage between terminals No. 7 (Light Blue/White wire) and No. 16 (Orange wire) at DLC. See Figure. Also, measure voltage between terminals No. 7 (Light Blue/White wire) and No. 4 (Black wire) at DLC. If any reading indicates voltage, go to next step. If both readings indicate zero volts, go to step  22.
  7. Turn ignition off. Reconnect bulkhead connector C148. If vehicle is equipped with an air suspension control module, go to next step. If vehicle is not equipped with an air suspension control module, go to step  9.
  8. Disconnect air suspension control module connector C2000 located left center of instrument panel. See Figure. Turn ignition on. Measure voltage between terminals No. 7 (Light Blue/White wire) and No. 16 (Orange wire) at DLC. See Figure. Also, measure voltage between terminals No. 7 (Light Blue/White wire) and No. 4 (Black wire) at DLC. If any reading indicates voltage, go to next step. If both readings indicate zero volts, replace air suspension control module and retest system for normal operation.
  9. Turn ignition off. Reconnect air suspension control module connector C2000. Disconnect GEM/CTM 26-pin connector C280 located behind center of instrument panel. See Figure. Turn ignition on. Measure voltage between terminals No. 7 (Light Blue/White wire) and No. 16 (Orange wire) at DLC. See Figure. Also, measure voltage between terminals No. 7 (Light Blue/White wire) and No. 4 (Black wire) at DLC. If any reading indicates voltage, go to next step. If both readings indicate zero volts, replace GEM/CTM and retest system for normal operation.
  10. Turn ignition off. Reconnect GEM/CTM 26-pin connector C280. Deactivate air bag system. See appropriate AIR BAG RESTRAINT SYSTEMS article. Disconnect Restraint Control Module (RCM) connector, located behind right kick panel. Turn ignition on. Measure voltage between terminals No. 7 (Light Blue/White wire) and No. 16 (Orange wire) at DLC. See Figure. Also, measure voltage between terminals No. 7 (Light Blue/White wire) and No. 4 (Black wire) at DLC. If any reading indicates voltage, repair circuit No. 70 (Light Blue/White wire). Retest system for normal operation. If both readings indicate zero volts, replace RCM and retest system for normal operation.
  11. Turn ignition off. Reconnect in-line connector C212. Check if vehicle is equipped with Remote Anti-Theft Personality (RAP) module. Rap is located behind left rear quarter panel. If vehicle is equipped with RAP module, go to next step. If vehicle is not equipped with RAP module, go to step  13.
  12. Disconnect RAP module 26-pin connector C336. Turn ignition on. Measure voltage between terminals No. 7 (Light Blue/White wire) and No. 16 (Orange wire) at DLC. See Figure. Also, measure voltage between terminals No. 7 (Light Blue/White wire) and No. 4 (Black wire) at DLC. If any reading indicates voltage, go to next step. If both readings indicate zero volts, replace RAP module and retest system for normal operation.
  13. Turn ignition off. Reconnect RAP module 26-pin connector C336. Check if vehicle is equipped with Parking Aid Module (PAM). PAM is located behind spare tire. If vehicle is equipped with PAM, go to next step. If vehicle is not equipped with PAM, go to step  15.
  14. Disconnect PAM 24-pin connector C440. Turn ignition on. Measure voltage between terminals No. 7 (Light Blue/White wire) and No. 16 (Orange wire) at DLC. See Figure. Also, measure voltage between terminals No. 7 (Light Blue/White wire) and No. 4 (Black wire) at DLC. If any reading indicates voltage, go to next step. If both readings indicate zero volts, replace PAM and retest system for normal operation.
  15. Turn ignition off. Reconnect PAM 24-pin connector C440. Check if vehicle is equipped with Driver's Seat Module (DSM). DSM is located under driver's seat. If vehicle is equipped with DSM, go to next step. If vehicle is not equipped with DSM, go to step  17.
  16. Disconnect DSM 22-pin connector C337. Turn ignition on. Measure voltage between terminals No. 7 (Light Blue/White wire) and No. 16 (Orange wire) at DLC. See Figure. Also, measure voltage between terminals No. 7 (Light Blue/White wire) and No. 4 (Black wire) at DLC. If any reading indicates voltage, go to next step. If both readings indicate zero volts, replace DSM and retest system for normal operation.
  17. Turn ignition off. Reconnect DSM connector C337. Disconnect in-line connector C346 located under of left front of driver's seat. Turn ignition on. Measure voltage between terminals No. 7 (Light Blue/White wire) and No. 16 (Orange wire) at DLC. See Figure. Also, measure voltage between terminals No. 7 (Light Blue/White wire) and No. 4 (Black wire) at DLC. If any reading indicates voltage, repair circuit No. 70 (Light Blue/White wire) between in-line connector C212, in-line connector C346 and RAP module connector. Retest system for normal operation. If both readings indicate zero volts, repair circuit No. 70 (Light Blue/White wire) between in-line connector C346 and DSM connector. Retest system for normal operation.
  18. Turn ignition off. Reconnect in-line connector C212. Disconnect RAP module 26-pin connector C336 located behind left rear quarter panel. Turn ignition on. Measure voltage between terminals No. 7 (Light Blue/White wire) and No. 16 (Orange wire) at DLC. See Figure. Also, measure voltage between terminals No. 7 (Light Blue/White wire) and No. 4 (Black wire) at DLC. If any reading indicates voltage, repair circuit No. 70 (Light Blue/White wire) between in-line connector C212 and RAP module connector. Retest system for normal operation. If both readings indicate zero volts, replace RAP module and retest system for normal operation.
  19. Turn ignition off. Reconnect in-line connector C212. Disconnect PAM 26-pin connector C440 located behind spare tire. Turn ignition on. Measure voltage between terminals No. 7 (Light Blue/White wire) and No. 16 (Orange wire) at DLC. See Figure. Also, measure voltage between terminals No. 7 (Light Blue/White wire) and No. 4 (Black wire) at DLC. If any reading indicates voltage, repair circuit No. 70 (Light Blue/White wire) between in-line connector C212 and PAM connector. If both readings indicate zero volts, replace PAM and retest system for normal operation.
  20. Turn ignition off. Reconnect PAM 26-pin connector C440. Disconnect DSM 22-pin connector C337 located under driver's seat. Turn ignition on. Measure voltage between terminals No. 7 (Light Blue/White wire) and No. 16 (Orange wire) at DLC. See Figure. Also, measure voltage between terminals No. 7 (Light Blue/White wire) and No. 4 (Black wire) at DLC. If any reading indicates voltage, go to next step. If both readings indicate zero volts, replace DSM and retest system for normal operation.
  21. Turn ignition off. Disconnect in-line connector C346 located under left front of driver's seat. Turn ignition on. Measure voltage between terminals No. 7 (Light Blue/White wire) and No. 16 (Orange wire) at DLC. See Figure. Also, measure voltage between terminals No. 7 (Light Blue/White wire) and No. 4 (Black wire) at DLC. If any reading indicates voltage, repair circuit No. 70 (Light Blue/White wire) between in-line connector C212 and in-line connector C346. Retest system for normal operation. If both readings indicate zero volts, repair circuit No. 70 (Light Blue/White wire) between in-line connector C346 and DSM connector. Retest system for normal operation.
  22. Turn ignition off. Reconnect 40-pin bulkhead connector C148. Disconnect 4WABS module connector located at left front of engine compartment. Turn ignition on. Measure voltage between terminals No. 7 (Light Blue/White wire) and No. 16 (Orange wire) at DLC. See Figure. Also, measure voltage between terminals No. 7 (Light Blue/White wire) and No. 4 (Black wire) at DLC. If any reading indicates voltage, go to next step. If both readings indicate zero volts, replace 4WABS module and retest system for normal operation.
  23. Turn ignition off. Disconnect in-line 12-pin connector C140 located at left front of engine compartment, near 4WABS module connector. Turn ignition on. Measure voltage between terminals No. 7 (Light Blue/White wire) and No. 16 (Orange wire) at DLC. See Figure. Also, measure voltage between terminals No. 7 (Light Blue/White wire) and No. 4 (Black wire) at DLC. If any reading indicates voltage, repair circuit No. 70 (Light Blue/White wire) between in-line connector C148 and in-line connector C140. Retest system for normal operation. If both readings indicate zero volts, repair circuit No. 70 (Light Blue/White wire) between in-line connector C140 and 4WABS. Retest system for normal operation.
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