Test G: No Module/Network Communication - No Power To NGS Tester

1. Turn ignition switch to LOCK position. Measure voltage at terminal No. 16 (Orange wire) at Data Link Connector (DLC). See Figure . If battery voltage does not exist, go to next step. If battery voltage exists, go to step  4 .
2. Remove fuse No. 28 (30-amp) from instrument panel fuse box. Inspect fuse. If fuse is okay, go to next step. If fuse is blown, repair short to ground in power distribution circuit as necessary. See appropriate wiring diagram in POWER DISTRIBUTION article in WIRING DIAGRAMS.
3. Disconnect instrument panel fuse box harness connector C371. See Fig 1 . Measure voltage at terminal No. 3 at instrument panel fuse box connect C371 (fuse box side). If battery voltage exists, repair open in Orange wire between instrument panel fuse box and DLC. If battery voltage does not exist, replace instrument panel fuse box.
4. Measure resistance between ground and terminal No. 5 (Black/Orange wire) at DLC. If resistance is 5 ohms or less, go to next step. If resistance is greater than 5 ohms, repair open in Black/Orange wire.
5. Measure resistance between ground and terminal No. 4 (Black wire) at DLC. If resistance is 5 ohms or less, problem is with NGS tester. If resistance is greater than 5 ohms, repair open in Black wire.

Fig 1: Identifying Instrument Panel Fuse Box Harness Connectors

Courtesy of FORD MOTOR CO.