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Data Link Diagnostic Test

  1. Connect New Generation Star (NGS) tester to Data Link Connector (DLC), if not already connected. Select vehicle to be tested from NGS tester menu.
  2. Turn ignition switch to RUN position. Rotate dial on NGS tester to menu item DIAGNOSTIC DATA LINK and press trigger. A test will be performed on the BUS (circuits No. 914 and 915) for the module communications network and the ISO 9141 communication link (circuit No. 70). This is the Light Blue/White wire that is between terminal No. 7 on DLC and the electronic crash sensor module, driver's door module and lighting control module.
  3. If NGS tester displays CKT 914 (+) = SYSTEM PASSED and CKT 915 (-) = SYSTEM PASSED, module communications network is okay. If NGS tester displays CKT 70 = SYSTEM PASSED, ISO 9141 communication link is operating properly. Return to article that directed you here and continue diagnosis.
  4. If NGS tester does not display CKT 914 (+) = SYSTEM PASSED, CKT 915 (-) = SYSTEM PASSED and CKT 70 = SYSTEM PASSED, perform the following as applicable.
SYMPTOM CHART

Symptom Perform Test
Anti-Lock Brake System (ABS) Module Does Not Respond To NGS Tester A 
Lighting Control Module (LCM) Does Not Respond To NGS Tester B 
Driver's Door Module (DDM) Does Not Respond To NGS Tester C 
Natural Gas Vehicle (NGV) Module Does Not Respond To NGS Tester D 
Electronic Automatic Temperature Control (EATC) Module Does Not Respond To NGS Tester E 
Electronic Crash Sensor (ECS) Module Does Not Respond To NGS Tester F 
Powertrain Control Module (PCM) Does Not Respond To NGS Tester G 
Passive Anti-Theft System (PATS) Module Does Not Respond To NGS Tester H 
No Module/Network Communication - ISO 9141 Link I 
No Module/Network Communication - BUS Link J 
No Module/Network Communication K