WARNING: This page is about a different car, the 1997 Mercury Grand Marquis and 1997 Ford Crown Victoria. However, it is still accessible from the selected car via links, so may be relevant.

NOTE: Ignition switch must be in RUN position or test will fail.

Connect New Generation Star (NGS) scan tester on Data Link Connector (DLC) and perform proper hook-up procedure. See EQUIPMENT HOOK-UP . Turn ignition switch to RUN position. Rotate dial on scan 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 goes between terminal No. 7 on DLC and Lighting Control Module (LCM), Anti-Lock Brake System (ABS) Module, Air Bag Diagnostic Monitor, and Driver's Door Module (DDM).
If scan tester displays CKT 914 (+) = SYSTEM PASSED and CKT 915 (-) = SYSTEM PASSED, module communications network is okay. If scan tester displays CKT 70 = SYSTEM PASSED, ISO 9141 communication link is operating properly.
If scan tester does not display CKT 914 (+) = SYSTEM PASSED, CKT 915 (-) = SYSTEM PASSED and CKT 70 = SYSTEM PASSED, go to COMMUNICATION SYSTEM DIAGNOSTICS .

When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

• You smell fuel, burning insulation, or see smoke.

• Brakes feel soft, pull hard to one side, or make grinding noises.

• The engine overheats, stalls repeatedly, or misfires under load.

• You are missing required tools, torque specs, or safe lifting equipment.

• You are not confident in the next step or safety outcome.

Safety Warning

Data Link Diagnostics

Use the Manual With the Right Hardware

When to See a Mechanic

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