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Test G: No Module/Network Communication - ISO 9141 Network

  1. Turn ignition switch to OFF position. Inspect 16-pin Data Link Connector (DLC) for physical damage, bent terminals or corrosion. DLC is located below steering column. Pay particular attention to DLC terminal No. 7 (Light Blue/White wire). Repair DLC as necessary and retest system for normal operation. If DLC is okay, go to next step.
  2. Disconnect 20-pin Generic Electronic Module (GEM) harness connector C201A (2.5L engine) or C2100A (all other engines) located behind center of instrument panel. On 2.5L engines, measure resistance in Light Blue/White wire between GEM harness connector C201A terminal No. 25 and DLC terminal No. 7. On all other engines, measure resistance in Light Blue/White wire between GEM harness connector C2100A terminal No. 3 and DLC terminal No. 7. See Figure and Figure . If resistance is less than 5 ohms, go to next step. If resistance is more than 5 ohms, repair open in Light Blue/White wire between GEM and DLC, and retest system for normal operation.
  3. Connect New Generation Star (NGS) tester to DLC. Turn ignition switch to RUN position. Perform DATA LINK DIAGNOSTIC TEST  . If NGS tester does not indicate SYSTEM PASSED, go to next step. If NGS tester indicates SYSTEM PASSED, go to step  12 .
  4. Turn ignition switch to OFF position. Connnect GEM harness connector C201A (2.5L engine) or C2100A (all other engines). Disconnect 17-pin 4-Wheel Drive (4WD) control module harness connector C281A, located behind right side kick panel. See Figure . Measure resistance in Light Blue/White wire between 4WD harness connector C281A terminal No. 4 and DLC terminal No. 7. See Figure and Figure . If resistance is less than 5 ohms, go to next step. If resistance is more than 5 ohms, repair open in Light Blue/White wire between 4WD control module and DLC. Retest system for normal operation.
  5. Turn ignition switch to RUN position. Perform DATA LINK DIAGNOSTIC TEST  . If NGS tester does not indicate SYSTEM PASSED, go to next step. If NGS tester indicates SYSTEM PASSED, go to step  13 .
  6. Turn ignition switch to OFF position. Connect 4WD control module harness connector C281A. Disconnect 26-pin Central Security Module (CSM) connector C274A located behind right side of instrument panel. Measure resistance in Light Blue/White wire between CSM harness connector C274A terminal No. 3 and DLC terminal No. 7. See Figure and Figure . If resistance is less than 5 ohms, go to next step. If resistance is more than 5 ohms, repair open in Light Blue/White wire between CSM and DLC. Retest system for normal operation.
  7. Turn ignition switch to RUN position. Perform DATA LINK DIAGNOSTIC TEST  . If NGS tester does not indicate SYSTEM PASSED, go to next step. If NGS tester indicates SYSTEM PASSED, go to step  14 .
  8. Turn ignition switch to OFF position. Connect CSM harness connector C274A. Deactivate air bag system. See DISABLING & ACTIVATING AIR BAG SYSTEM in AIR BAG RESTRAINT SYSTEMS - RANGER article. Disconnect 26-pin Restraints Control Module (RCM) harness connector C2041 located behind left side of instrument panel. Measure resistance in Light Blue/White wire between RCM harness connector C2041 terminal No. 5 and DLC terminal No. 7. See Figure and Figure . If resistance is less than 5 ohms, go to next step. If resistance is more than 5 ohms, repair open in Light Blue/White wire between RCM and DLC. Retest system for normal operation.
  9. Turn ignition switch to RUN position. Perform DATA LINK DIAGNOSTIC TEST  . If NGS tester does not indicate SYSTEM PASSED, go to next step. If NGS tester indicates SYSTEM PASSED, go to step  15
  10. Connect RCM harness connector C2041. Disconnect 25-pin 4-Wheel Anti-Lock Brake System (4WABS) module harness connector C135 located at front left side of engine compartment. See Figure . Measure resistance in Light Blue/White wire between 4WABS module harness connector C135 terminal No. 23 and DLC terminal No. 7. See Figure and Figure . If resistance is less than 5 ohms, go to next step. If resistance is more than 5 ohms, repair open in Light Blue/White wire between 4WABS control module and DLC. Retest system for normal operation.
  11. Turn ignition switch to RUN position. Perform DATA LINK DIAGNOSTIC TEST  . 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.
  12. Disconnect all GEM harness connectors. Inspect GEM harness connectors for physical damage, bent terminals or corrosion. Repair GEM harness connectors as necessary. Reconnect all GEM harness connectors. Retest system for normal operation. If problem still exists, replace GEM. Perform DATA LINK DIAGNOSTIC TEST  . If problem no longer exists, system is okay at this time.
  13. Disconnect all 4WD control module harness connectors. Inspect 4WD control module harness connectors for physical damage, bent terminals or corrosion. Repair 4WD control module harness connectors as necessary. Reconnect all 4WD control module harness connectors. Retest system for normal operation. If problem still exists, replace 4WD control module. Perform DATA LINK DIAGNOSTIC TEST  . If problem no longer exists, system is okay at this time.
  14. Disconnect all CSM harness connectors. Inspect CSM harness connectors for physical damage, bent terminals or corrosion. Repair CSM harness connectors as necessary. Reconnect all GEM harness connectors. Retest system for normal operation. If problem still exists, replace CSM. Perform DATA LINK DIAGNOSTIC TEST  . If problem no longer exists, system is okay at this time.
  15. Disconnect 26-pin RCM harness connector C2041. Inspect RCM harness connectors for physical damage, bent terminals or corrosion. See Figure . Repair RCM harness connectors as necessary. Reconnect RCM harness connector C2041. Retest system for normal operation. If problem still exists, replace RCM. Perform DATA LINK DIAGNOSTIC TEST  . If problem no longer exists, system is okay at this time.
  16. Disconnect all 4WABS module harness connectors. Inspect 4WABS harness connectors for physical damage, bent terminals or corrosion. See Figure . Repair 4WABS harness connectors as necessary. Reconnect all 4WABS module harness connectors. Retest system for normal operation. If problem still exists, replace 4WABS module. Perform DATA LINK DIAGNOSTIC TEST  . If problem no longer exists, system is okay at this time.
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