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Test C: Driver's Door Module (DDM) Does Not Respond To NGS Tester

WARNING: This page is about a different car, the 1999 Lincoln Town Car. However, it is still accessible from the selected car via links, so may be relevant.
  1. Turn ignition switch to LOCK position. Disconnect DDM 22-pin harness connector C520 located inside driver's door. Inspect harness connector for loose, damaged or corroded terminals. Repair as necessary and retest system for normal operation. If harness connector is okay, reconnect harness connector. Turn ignition switch to RUN position. Perform data link diagnostic test. See DATA LINK DIAGNOSTIC TEST  under SELF-DIAGNOSTIC SYSTEM. If NGS tester indicates DDM: NO RESPONSE ON CKT 914 (BUS +), go to next step. If NGS tester does not indicate DDM: NO RESPONSE ON CKT 914 (BUS +), go to step  4.
  2. Turn ignition switch to LOCK position. Disconnect NGS tester. Disconnect DDM harness connector C520. Measure resistance in Tan/Orange wire between terminal No. 35 at DDM harness connector C520 and terminal No. 2 at Data Link Connector (DLC). See Figure and Fig 1 . If resistance is less than 5 ohms, replace DDM and retest system for normal operation. If resistance is 5 ohms or greater, go to next step.
  3. Disconnect 42-pin harness connector C202 located behind right side of instrument panel. See Figure. Inspect harness connector for loose, damaged or corroded terminals. Repair as necessary and retest system for normal operation. If harness connector is okay, measure resistance in Tan/Orange wire between terminal No. 6 at male half of harness connector C202 and terminal No. 2 at DLC. See Figure and Fig 2 . If resistance is less than 5 ohms, repair open in Tan/Orange wire between DDM harness connector C520 and harness connector C202. Retest system for normal operation. If resistance is 5 ohms or greater, repair open in Tan/Orange wire between harness connector C202 and DLC. Retest system for normal operation.
  4. Turn ignition switch to LOCK position. Disconnect NGS tester. Disconnect DDM harness connector C520. Measure resistance in Pink/Light Blue wire between terminal No. 36 at DDM harness connector C520 and terminal No. 10 at DLC. See Figure and Fig 2 . If resistance is less than 5 ohms, replace DDM and retest system for normal operation. If resistance is 5 ohms or greater, go to next step.
  5. Disconnect 42-pin harness connector C202 located behind right side of instrument panel. See Figure. Inspect harness connector for loose, damaged or corroded terminals. Repair as necessary and retest system for normal operation. If harness connector is okay, measure resistance in Pink/Light Blue wire between terminal No. 7 at male half of harness connector C202 and terminal No. 10 at DLC. See Figure and Fig 2 . If resistance is less than 5 ohms, repair open in Pink/Light Blue wire between DDM harness connector C520 and harness connector C202. Retest system for normal operation. If resistance is 5 ohms or greater, repair open in Pink/Light Blue wire between harness connector C202 and DLC. Retest system for normal operation.
Fig 1: Identifying DDM Harness Connector C520 Terminals
G98F01714Courtesy of FORD MOTOR CO.
Fig 2: Identifying Harness Connector C202 Terminals (Male Half Shown)
G98I01715Courtesy of FORD MOTOR CO.
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