Data Link Diagnostic Test

Connect Worldwide Diagnostic System (WDS) tester or New Generation Star (NGS) tester to Data Link Connector (DLC), located under instrument panel between steering column and radio. See Figure. Select vehicle to be tested from diagnostic tool menu.
Turn ignition switch to RUN position. Rotate dial on WDS or NGS tester to menu item DIAGNOSTIC DATA LINK and press trigger. A test will be performed on bus (circuits No. 914 and 915) for module communications network and ISO 9141 communication link (circuit No. 70).
If WDS or NGS tester displays CKT 914 (+) = SYSTEM PASSED and CKT 915 (-) = SYSTEM PASSED, module communications network is okay. Also if WDS or NGS tester displays CKT 70 = SYSTEM PASSED, ISO 9141 communication link is operating properly. Return to article that directed you here and continue diagnosis.
If WDS or NGS tester does not display CKT 914 (+) = SYSTEM PASSED, CKT 915 (-) = SYSTEM PASSED and CKT 70 = SYSTEM PASSED, perform the following as applicable.
- If no response from WDS or NGS tester, perform TEST H: NO MODULE/NETWORK COMMUNICATION under SYSTEM TESTS.
- If WDS or NGS tester displays CKT 70, CKT 914 and/or CKT 915 = SOME ECUS NO RESP/NOT EQUIP, perform appropriate test for module not responding. See SYMPTOM INDEX table.
- If WDS or NGS tester displays CKT 70 = ALL ECUS NO RESP/NOT EQUIP, perform TEST G: NO MODULE/NETWORK COMMUNICATION - ISO 9141 LINK under SYSTEM TESTS.
- If WDS or NGS tester displays CKT 914 = ALL ECUS NO RESP/NOT EQUIP, perform TEST F: NO MODULE/NETWORK COMMUNICATION - SCP BUS LINK under SYSTEM TESTS.
- If WDS or NGS tester displays CKT 915 = ALL ECUS NO RESP/NOT EQUIP, perform TEST F: NO MODULE/NETWORK COMMUNICATION - SCP BUS LINK under SYSTEM TESTS.
- If module in question is NO RESPONSE/NOT EQUIPPED, perform appropriate test for module not responding. See SYMPTOM INDEX table.
- If module in question is NO RESPONSE ON CKT 914 (BUS +), perform appropriate test for module not responding. See SYMPTOM INDEX table.
- If module in question is NO RESPONSE ON CKT 915 (BUS -), perform appropriate test for module not responding. See SYMPTOM INDEX table.