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Test E: Doors Do Not Lock/Unlock Using Keyless Entry Keypad

  1. Using driver's side door lock control switch, lock and unlock doors. If doors operate correctly, go to next step. If door locks do not operate correctly, diagnose by symptom. See SYMPTOM INDEX  table.
  2. Turn ignition switch to LOCK position. Connect New Generation Star (NGS) tester to Data Link Connector (DLC). DLC is located below left side of instrument panel, right of steering column. Turn ignition switch to RUN position. Perform Central Security Module (CSM) self-test. If DTC B1526 is retrieved, go to next step. If DTC B1526 is not retrieved, go to step  5.
  3. Turn ignition switch to LOCK position. Disconnect negative battery cable. Disconnect CSM harness connector C256. CSM is located behind left side of instrument panel. Measure resistance between ground and CSM harness connector C256 terminals No. 5 (Light Blue/Yellow wire), No. 6 (Light Green/Red wire) and No. 19 (Yellow/Black wire). See Figure. If resistance is 10 k/ohms or less, go to next step. If resistance is more than 10 k/ohms, go to step  9.
  4. Remove left front door panel trim. Disconnect keyless entry keypad harness connector C514. Measure resistance between ground and CSM harness connector C256 terminals No. 5 (Light Blue/Yellow wire), No. 6 (Light Green/Red wire) and No. 19 (Yellow/Black wire). See Figure. If resistance is more than 10 k/ohms at each terminal, replace keyless entry keypad. If resistance is 10 k/ohms or less at any terminal, repair open in appropriate wire. See WIRING DIAGRAMS .
  5. Using NGS tester, retrieve keyless entry code from CSM. If code retrieved from CSM matches factory sticker, go to next step. If code retrieved does not match factory sticker, use factory code and program keyless entry keypad and retest system. See KEYLESS ENTRY KEYPAD  under PROGRAMMING.
  6. While pressing 1/2 button on keyless entry keypad, measure resistance between ground and CSM harness connector C256 terminal No. 5 (Light Blue/Yellow wire). While pressing 3/4 button on keyless entry keypad, measure resistance between ground and CSM harness connector C256 terminal No. 6 (Light Green/Red wire). While pressing 7/8 button on keyless entry keypad, measure resistance between ground and CSM harness connector C256 terminal No. 7 (Yellow wire). While pressing 9/0 button on keyless entry keypad, measure resistance between ground and CSM harness connector C256 terminal No. 8 (Red wire). While pressing 5/6 button on keyless entry keypad, measure resistance between ground and CSM harness connector C256 terminal No. 19 (Yellow/Black wire). See Figure. If resistance is more than 5 ohms at any terminal, go to next step. If resistance is 5 ohms or less at all terminals, go to step  9.
  7. Disconnect keyless entry keypad harness connector C514. Measure resistance in Brown wire between keyless entry keypad harness connector C514 terminal No. 8 and CSM harness connector C256 terminal No. 15. See Figure and Fig 1 . If resistance is 5 ohms or less, go to next step. If resistance is more than 5 ohms, repair open in Brown wire between CSM harness connector and keyless entry keypad harness connector. See WIRING DIAGRAMS .
    8. NOTE: All testing in this step is done between CSM harness connector C256 and keyless entry keypad harness connector C514.
  8. Measure resistance in Light Blue/Yellow wire between CSM terminal No. 5 and keypad terminal No. 3. Measure resistance in Light Green/Red wire between CSM terminal No. 6 and keypad terminal No. 4. Measure resistance in Yellow/Black wire between CSM terminal No. 19 and keypad terminal No. 5. Measure resistance in Yellow wire between CSM terminal No. 7 and keypad terminal No. 6. Measure resistance in Red wire between CSM terminal No. 8 and keypad terminal No. 1. See Figure and Fig 1 . If resistance is 5 ohms or less at all test points, replace keyless entry keypad. See KEYLESS ENTRY KEYPAD  under REMOVAL & INSTALLATION. If resistance is more than 5 ohms at any test point, repair open in appropriate wire. See WIRING DIAGRAMS .
  9. Disconnect all CSM harness connectors. Inspect harness connectors for corrosion and pushed out pins. Connect all CSM harness connectors, ensuring they are connected correctly. Operate system and verify if problem is still exists. If problem is still exists, replace CSM. See CENTRAL SECURITY MODULE  under REMOVAL & INSTALLATION. If problem does not exist, system is operating correctly at this time. Clear DTCs and perform CSM self-test.
Fig 1: Identifying Keyless Entry Keypad Harness Connector C514 Terminals
G00009225Courtesy of FORD MOTOR CO.
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