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Test A: No Communication With Driver's Door Module

  1. Ensure transmission is in Park. Turn ignition switch to LOCK position. Check fuse No. 30 (7.5-amp) in instrument panel fuse box. If fuse is okay, go to next step. If fuse is blown, go to step  5 .
  2. Measure voltage at input side of fuse No. 30. If battery voltage exists, go to next step. If battery voltage does not exist, go to step  20 .
  3. Ensure ignition switch is in LOCK position. Remove fuse No. 30 (7.5-amp) in instrument panel fuse box. Disconnect Driver's Door Module (DDM) harness connector C520. Measure resistance in Light Green/Violet wire between output side of fuse No. 30 and terminal No. 29 at DDM harness connector C520. See Fig 1 . If resistance is 5 ohms or less, go to next step. If resistance is greater than 5 ohms, repair open in Light Green/Violet wire between instrument panel fuse box and DDM.
  4. Measure resistance between ground and terminal No. 23 (Pink/Orange wire) at DDM harness connector C520. If resistance is greater than 5 ohms, repair open in Pink/Orange wire. If resistance is 5 ohms or less, repair module communications concern. See MODULE COMMUNICATIONS NETWORK article.
  5. Replace fuse No. 30. DO NOT operate power seat switch. If fuse blows, go to next step. If fuse does not blow, go to step  9 .
  6. Ensure ignition switch is in LOCK position. Remove fuse No. 30 from instrument panel fuse box. Disconnect DDM harness connector C520 and Driver's Seat Module (DSM) harness connector C313. Measure resistance between ground and terminal No. 29 (Light Green/Violet wire) at DDM harness connector C520. See Fig 1 . If resistance is 10 k/ohms or less, go to next step. If resistance is greater than 10 k/ohms, go to step  8 .
  7. Test driver's and passenger's door lock switches. Test remote trunk lock switch. Test mirror control switch. Test seat control switches. See appropriate test under COMPONENT TESTS  . If no switch is defective, repair short to ground in Light Green/Violet wire. If any switch is defective, replace appropriate switch.
  8. Ensure ignition switch is in LOCK position. Connect DSM harness connector C313. Measure resistance between ground and terminal No. 29 (Light Green/Violet wire) at DDM harness connector C520. If resistance is greater than 10 k/ohms, replace driver's door module. If resistance is 10 k/ohms or less, replace driver's seat module.
  9. Lock and unlock doors at all door lock switches. If fuse No. 30 blows, go to next step. If fuse No. 30 does not blow, go to step  12 .
  10. Remove door lock switches. Test all door lock switches. See DOOR LOCK SWITCH  under COMPONENT TESTS. If all door lock switches are okay, go to next step. If any door lock switch is defective, replace appropriate door lock switch.
  11. Ensure ignition switch is in LOCK position. Disconnect Driver's Door Module (DDM) harness connector C520. Disconnect driver's door lock switch harness connector C503. Disconnect passenger's door lock switch harness connector C603. Measure resistance between ground and terminal No. 2 (Pink/Yellow wire) at driver's door lock switch harness connector C503. See Fig 2 . Also, measure resistance between ground and terminal No. 6 (Pink/Light Green wire) at driver's door lock switch harness connector C503. If either or both resistance reading are 10 k/ohms or less, repair short to ground in appropriate wire(s). If both resistance readings are greater than 10 k/ohms, replace driver's door module.
  12. Activate mirrors in all directions. If fuse No. 30 blows, go to next step. If fuse No. 30 does not blow, go to step  15 .
  13. Remove mirror control switch. Test mirror control switch. See MIRROR CONTROL SWITCH  under COMPONENT TESTS. If mirror control switch is okay, go to next step. If mirror control switch is defective, replace mirror control switch.
  14. Ensure ignition switch is in LOCK position. Disconnect Driver's Door Module (DDM) harness connector C520. Disconnect mirror control switch harness connector C550. Measure resistance between ground and appropriate terminals at mirror control switch harness connector C550. See MIRROR CONTROL SWITCH TERMINAL IDENTIFICATION  table. See Fig 3 . If all resistance readings are greater than 10 k/ohms, replace driver's door module. If any resistance reading is 10 k/ohms or less, repair short to ground in appropriate wire.
    MIRROR CONTROL SWITCH TERMINAL IDENTIFICATION

    Terminal No. Wire Color
    1 Red/Orange
    2 Dark Green/Orange
    4 Yellow/Black
    8 Violet/Orange
    9 Dark Blue/Orange
  15. Activate memory switch through all positions. If fuse No. 30 blows, go to next step. If fuse No. 30 does not blow, go to step  18 .
  16. Remove driver's seat control switch. Test memory portion of driver's seat control switch. See DRIVER'S SEAT CONTROL SWITCH (WITH MEMORY)  under COMPONENT TESTS. If memory switch is okay, go to next step. If memory switch is defective, replace driver's seat control switch.
  17. Ensure ignition switch is in LOCK position. Disconnect Driver's Door Module (DDM) harness connectors C520 and C521. Measure resistance between ground and appropriate terminals at driver's seat control switch harness connector C509. See SEAT SWITCH CIRCUIT IDENTIFICATION  table. See Fig 4 . If all resistance readings are greater than 10 k/ohms, replace driver's door module. If any resistance readings are 10 k/ohms or less, repair short to ground in appropriate wire.
    SEAT SWITCH CIRCUIT IDENTIFICATION

    Terminal No. Wire Color
    4 White/Orange
    5 Brown/Orange
    6 Brown/Light Green
    7 Black/Orange
  18. Activate driver's seat control switch in all directions. If fuse No. 30 blows, go to next step. If fuse No. 30 does not blow, system is okay at this time.
  19. Ensure ignition switch is in LOCK position. Disconnect Driver's Door Module (DDM) harness connector C521. Disconnect driver's seat control switch harness connector C509. Measure resistance between ground and appropriate terminals at driver's seat control switch harness connector C509. See DRIVER'S SEAT CONTROL SWITCH TERMINAL IDENTIFICATION  table. See Fig 4 . If all resistance readings are greater than 10 k/ohms, replace driver's door module. If any resistance readings are 10 k/ohms or less, repair short to ground in appropriate wire.
    DRIVER'S SEAT CONTROL SWITCH TERMINAL IDENTIFICATION

    Terminal No. Wire Color
    1 Yellow/White
    2 Red/Light Blue
    3 Yellow/Light Blue
    9 Red/White
    11 Yellow/Light Green
    12 Red/Light Green
    13 Gray
    14 Gray/Black
  20. Remove maxi-fuse No. 8 (30-amp) from power distribution box. Measure voltage at input side of maxi-fuse No. 8 at power distribution box. If battery voltage exists, go to next step. If battery voltage does not exist, repair power supply to maxi-fuse No. 8. See POWER DISTRIBUTION in appropriate SYSTEM WIRING DIAGRAMS ARTICLE in ELECTRICAL.
  21. Ensure ignition switch is in LOCK position. Ensure maxi-fuse No. 8 is still removed. Remove fuse No. 30 (7.5-amp) from instrument panel fuse box. Disconnect Driver's Seat Module (DSM) harness connector C337. Measure resistance in Red wire between output side of maxi-fuse No. 8 and input side of fuse No. 30. If resistance is 5 ohms or less, go to next step. If resistance is greater than 5 ohms, repair open in Red wire.
  22. Measure resistance between ground and output side of maxi-fuse No. 8 at power distribution box. If resistance is greater than 10 k/ohms, go to next step. If resistance is 10 k/ohms or less, repair short to ground in Red wire.
  23. Ensure ignition switch is in LOCK position. Install maxi-fuse No. 8 in power distribution box. Install fuse No. 30 in instrument panel fuse box. Connect DSM harness connector C337. Operate driver's power seat in all directions. If driver's power seat operates properly in all directions, go to next step. If driver's power seat does not operate properly in all directions, replace driver's seat module.
  24. Inspect DSM for water damage. If water damage does not exist, go to next step. If water damage exists, replace driver's seat module.
  25. Turn ignition switch to RUN position. Operate driver's power window, power mirror and door lock switches in all directions. If maxi-fuse No. 8 blows, replace driver's door module. If maxi-fuse No. 8 does not blow, verify symptom and repair as necessary. See SYMPTOM CHART  table.
Fig 1: Identifying Driver's Door Module Harness Connector C520 Terminals
G98F01568Courtesy of FORD MOTOR CO.
Fig 2: Identifying Driver's Door Lock Switch Harness Connector C503 Terminals
G98D01567Courtesy of FORD MOTOR CO.
Fig 3: Identifying Mirror Control Switch Harness Connector C550 Terminals
G98G01578Courtesy of FORD MOTOR CO.
Fig 4: Identifying Driver's Seat Control Switch Harness Connector C509 Terminals
G98G01564Courtesy of FORD MOTOR CO.
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