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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). See Figure . This is the International Standards Organization (ISO) 9141 diagnostic communications network circuit.
  1. Turn ignition switch to LOCK position. Inspect Data Link Connector (DLC) terminal No. 7 (Light Blue/White wire) for looseness, damage or corrosion. See Figure . If terminal is damaged, repair as necessary. If terminal is not damaged, disconnect 26-pin Generic Electronic Module (GEM) harness connector C352. GEM is located behind instrument panel, next to central junction box. See Figure . Measure resistance in Light Blue/White wire between GEM harness connector C352 terminal No. 6 and DLC terminal No. 7. See Figure . If resistance is 5 ohms or less, go to next step. If resistance is more than 5 ohms, repair open in Light Blue/White wire between GEM and DLC. See DATA LINK CONNECTORS article in WIRING DIAGRAMS.
  2. Turn ignition switch to RUN position. Connect positive lead of a DVOM to DLC terminal No. 7 (Light Blue/White wire). See Figure . While observing voltage reading, connect negative lead of DVOM to DLC terminals No. 4 (Black wire), then No. 16 (Light Green/Red wire). If either measurement indicates zero volts, go to next step. If both measurements indicate voltage, replace GEM. See REMOVAL & INSTALLATION  .
  3. Turn ignition switch to LOCK position. Reconnect GEM harness connector C352. Disconnect 16-pin in-line harness connector C331. 16-pin in-line harness connector C331 is located near lower left "A" pillar. See Figure . Turn ignition switch to RUN position. Connect positive lead of a DVOM to DLC terminal No. 7 (Light Blue/White wire). While observing voltage reading, connect negative lead of DVOM to DLC terminals No. 4 (Black wire), then No. 16 (Light Green/Red wire). If either measurement indicates zero volts, go to next step. If both measurements indicate voltage, go to step  5 .
  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. RCM is located behind left center of instrument panel. See Figure . Turn ignition switch to RUN position. Connect positive lead of a DVOM to DLC terminal No. 7 (Light Blue/White wire). While observing voltage reading, connect negative lead of DVOM to DLC terminals No. 4 (Black wire), then No. 16 (Light Green/Red wire). If either measurement indicates zero volts, repair short in Light Blue/White wire between DLC, GEM, RCM and in-line harness connector C331. See DATA LINK CONNECTORS article in WIRING DIAGRAMS. If both measurements indicate voltage, replace RCM. See appropriate AIR BAG RESTRAINT SYSTEMS article.
  5. Turn ignition switch to LOCK position. Reconnect in-line harness connector C331. If vehicle is equipped with ABS (with or without traction control), go to next step. If vehicle is not equipped with ABS, go to step  7 .
  6. Disconnect Black 30-pin ABS module harness connector C141. ABS control module is located in right front of engine compartment, behind radiator. See Figure . Turn ignition switch to RUN position. Connect positive lead of a DVOM to DLC terminal No. 7 (Light Blue/White wire). While observing voltage reading, connect negative lead of DVOM to DLC terminals No. 4 (Black wire), then No. 16 (Light Green/Red wire). If either measurement indicates zero volts, go to next step. If both measurements indicate voltage, replace ABS control module. See REMOVAL & INSTALLATION  .
  7. Turn ignition switch to LOCK position. Disconnect Black 16-pin in-line harness connector C107. Black 16-pin in-line harness connector C107 is located in left rear corner of engine compartment. See Figure . Turn ignition switch to RUN position. Connect positive lead of a DVOM to DLC terminal No. 7 (Light Blue/White wire). While observing voltage reading, connect negative lead of DVOM to DLC terminals No. 4 (Black wire), then No. 16 (Light Green/Red wire). If either measurement indicates zero volts, repair short in Light Blue/White wire between in-line harness connectors C107 and C331. If both measurements indicate voltage, repair short in Light Blue/White wire between in-line harness connector C107 and ABS control module.
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