WARNING: This page is about a different car, the 2000 Ford Mustang. However, it is still accessible from the selected car via links, so may be relevant.

Inspect NGS tester connector for loose, damaged or corroded terminals. Repair connector as necessary and retest. If connector is okay, go to next step.
Turn ignition switch to LOCK position. Inspect Data Link Connector (DLC) for loose, damaged or corroded terminals. Repair connector as necessary and retest. If connector is okay, go to next step.
Measure voltage between ground and terminal No. 16 (Light Green/Red wire) at DLC. See Figure . If battery voltage exists, go to next step. If battery voltage does not exist, repair power distribution circuit as necessary. See POWER DISTRIBUTION article in WIRING DIAGRAMS.
Measure resistance between ground and terminals No. 4 (Black wire) and No. 5 (Blue/Yellow wire) at DLC. If both resistance readings are 5 ohms or less, repair or replace NGS tester. If either resistance reading is greater than 5 ohms, repair open in appropriate circuit between ground and DLC.

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

Test H: No Module/Network Communication

Use the Manual With the Right Hardware

When to See a Mechanic

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