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Test F: No Module/Network Communication - 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. Turn ignition switch to LOCK position. Inspect NGS tester connector for loose, damaged or corroded terminals. If connector is okay, go to next step. If problem exists, repair connector as necessary.
  2. Disconnect GEM module harness connector C352. Measure resistance in Light Blue/White wire between terminal No. 6 at GEM module harness connector C352 and terminal No. 7 at DLC. See Figure and Figure . If resistance is 5 ohms or less, go to next step. If resistance is greater than 5 ohms, repair open in Light Blue/White wire.
  3. Turn ignition switch to RUN position. Measure voltage between terminals No. 7 (Light Blue/White wire) and No. 4 (Black wire) at DLC. See Figure . Also, measure voltage between terminals No. 7 (Light Blue/White wire) and No. 16 (Light Green/Red wire) at DLC. If any reading indicates voltage, go to next step. If both readings indicate zero volts, replace GEM.
  4. Turn ignition switch to LOCK position. Disable air bag system. See appropriate AIR BAG RESTRAINT SYSTEMS article. Disconnect Restraint Control Module (RCM) harness connector C276. Turn ignition switch to RUN position. Measure voltage between terminals No. 7 (Light Blue/White wire) and No. 4 (Black wire) at DLC. Also, measure voltage between terminals No. 7 (Light Blue/White wire) and No. 16 (Light Green/Red wire) at DLC. If any reading indicates voltage, go to next step. If both readings indicate zero volts, replace RCM.
  5. If vehicle is equipped with ABS, go to next step. If vehicle is not equipped with ABS, repair short to voltage or ground in Light Blue/White wire.
  6. Turn ignition switch to LOCK position. Disconnect ABS module harness connector C141. Turn ignition switch to RUN position. Measure voltage between terminals No. 7 (Light Blue/White wire) and No. 4 (Black wire) at DLC. Also, measure voltage between terminals No. 7 (Light Blue/White wire) and No. 16 (Light Green/Red wire) at DLC. If any reading indicates voltage, go to next step. If both readings indicate zero volts, replace ABS.
  7. Turn ignition switch to LOCK position. Disconnect in-line harness connector C107. See Figure . Turn ignition switch to RUN position. Measure voltage between terminals No. 7 (Light Blue/White wire) and No. 4 (Black wire) at DLC. Also, measure voltage between terminals No. 7 (Light Blue/White wire) and No. 16 (Light Green/Red wire) at DLC. If any reading indicates voltage, go to next step. If both readings indicate zero volts, repair short to voltage or ground in Light Blue/White wire between ABS module and in-line harness connector C107.
  8. Turn ignition switch to LOCK position. Disconnect in-line harness connector C331. See Figure . Turn ignition switch to RUN position. Measure voltage between terminals No. 7 (Light Blue/White wire) and No. 4 (Black wire) at DLC. Also, measure voltage between terminals No. 7 (Light Blue/White wire) and No. 16 (Light Green/Red wire) at DLC. If any reading indicates voltage, repair short to voltage or ground in Light Blue/White wire between in-line harness connector C331 and DLC. If both readings indicate zero volts, repair short to voltage or ground in Light Blue/White wire between in-line harness connector C331 and in-line harness connector C107.
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