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Test F: All Locks Inoperative, 2-Step Unlock Does Not Operate Properly

  1. Turn ignition off. Connect New Generation Star (NGS) tester following manufacturer's instructions. Select GEM PID IGN_GEM. Turn ignition through all switch positions. If PID values agree with switch positions, go to next step. If PID values do not agree with switch positions, repair appropriate ignition switch circuit. See POWER DISTRIBUTION article in WIRING DIAGRAMS. Clear DTCs. Retest system.
  2. Retrieve continuous DTCs. Clear DTCs. Perform self-test. If no DTCs are retrieved, go to next step. If DTC B1834 or B1836 is retrieved, go to next step. If DTC B1833 is retrieved, go to step  13. If DTC B1342 is retrieved, replace GEM. Retest system.
  3. Using NGS tester, monitor GEM PID DD_UNLOCK while triggering GEM active command GEM DD_UNLOCK ON and OFF. If display agrees command, go to step  13. If display shows OFFO-G, go to next step. If display shows ON-B-, go to step  11.
  4. Turn ignition off. Disconnect door unlock relay connector from auxiliary relay box No. 2 located behind left rear trim panel above wheelwell. Measure voltage between ground and unlock relay connector Black/White wire terminal No. 1 (2-door) or No. 87A (4-door). See Figure. If voltage is more than 10 volts, go to next step. If voltage is less than 10 volts, check fuse No. 18 (25-amp) in instrument panel fuse block. If fuse is okay, repair Black/White wire(s). Clear DTCs and retest system.
  5. Check door unlock relay. See DOOR LOCK RELAY & DOOR UNLOCK RELAY  under COMPONENT TESTS. If relay is okay, go to next step. If relay is faulty, replace door unlock relay. Clear DTCs and retest system.
  6. Disconnect GEM C280 26-pin harness connector. Measure resistance of Pink/Light Green wire between door unlock relay connector terminal No. 2 (2-door) or No. 85 (4-door) and GEM C280 connector terminal No. 16. See Figure and Fig 1 . If resistance is less than 5 ohms, go to next step. If resistance is more than 5 ohms, repair open in Pink/Light Green wire. Retest system.
  7. Disconnect RAP C338 harness connector. Disconnect master door lock switch connector, passenger door lock switch connector and liftgate lock switch connector. Measure resistance of Pink/Light Green wire between ground and GEM C280 connector pin No. 16. See Fig 1. If resistance is more than 10 k/ohms, go to next step. If resistance is less than 10 k/ohms, repair short to ground in Pink/Light Green wire. Retest system.
    Fig 1: Identifying GEM/CTM Connector C280 Terminals
    G99I54880Courtesy of FORD MOTOR CO.
  8. Reconnect passenger door lock switch connector. Measure resistance of Pink/Light Green wire between ground and GEM C280 connector pin No. 16. If resistance is more than 10 k/ohms, go to next step. If resistance is less than 10 k/ohms, replace passenger door lock switch. Clear DTCs and retest system.
  9. Reconnect liftgate door lock switch connector C404. Measure resistance of between ground and GEM C280 connector pin No. 16 (Pink/Light Green wire). See Fig 1. If resistance is more than 10 k/ohms, go to next step. If resistance is less than 10 k/ohms, replace liftgate door lock switch. Clear DTCs and retest system.
  10. Reconnect master window/door lock switch connector C501. Measure resistance between ground and GEM C280 connector pin No. 16 (Pink/Light Green wire). If resistance is more than 10 k/ohms, replace GEM. Clear DTCs and retest system. If resistance is less than 10 k/ohms, replace master door lock switch. Clear DTCs and retest system.
  11. Turn ignition off. Disconnect door unlock relay. Turn ignition switch to RUN position. Measure voltage between ground and door unlock relay connector Pink/Light Green wire terminal. If any voltage exists, repair short to voltage in Pink/Light Green wire. Retest system. If no voltage exists, go to next step.
  12. Check door unlock relay. See DOOR LOCK RELAY & DOOR UNLOCK RELAY  under COMPONENT TESTS. If relay is okay, replace GEM. Clear DTCs and retest system. If relay is faulty, replace relay. Clear DTCs and retest system.
  13. Using NGS tester, monitor GEM PID DR_DSRM while unlocking all doors with ignition key. If PID display indicates L_DOOR when in unlock position and OFF when in lock position, replace GEM. Clear DTCs and retest system. If display indicates L_DOOR only, go to next step. If display indicates R_DOOR only, go to step  15. If display indicates LIFT_G only, go to step  16. If PID display indicates L_DOOR for all locks, go to step  17.
  14. Turn ignition off. Disconnect driver door disarm switch harness connector. Disconnect GEM 26-pin harness connector C280. Measure resistance of Dark Green/Violet wire between disarm switch connector and GEM connector C280. See Fig 1. Measure resistance of Black wire between ground and driver door disarm switch connector. If resistances are less than 5 ohms, replace disarm switch. Clear DTCs and retest system. If any resistance is more than 5 ohms, repair open in Dark Green/Violet and/or Black wire(s). Retest system.
  15. Turn ignition off. Disconnect passenger door disarm switch harness connector. Disconnect GEM C280 26-pin harness connector. Measure resistance of Dark Green/Violet wires between disarm switch connector and GEM C280 connector. Measure resistance of Black wire between door disarm switch connector and ground. If resistances are less than 5 ohms, replace disarm switch. Clear DTCs and retest system. If any resistance is more than 5 ohms, repair open in Dark Green/Violet and/or Black wire(s). Retest system.
  16. Turn ignition off. Disconnect liftgate door disarm switch harness connector. Disconnect GEM C280 26-pin harness connector. Measure resistance of Dark Green/Violet wire between disarm switch connector and GEM C280 connector. Measure resistance of Black wire between door disarm switch connector and ground. If resistances are less than 5 ohms, replace disarm switch. Clear DTCs and retest system. If any resistances is more than 5 ohms, repair open in Dark Green/Violet and/or Black wire(s). Retest system.
  17. Using NGS tester, monitor GEM PID DR_DSRM while disconnecting each door disarm switch. If PID display indicates OFF when any disarm switch is disconnected, replace disarm switch that changed value. If display did not indicate OFF, repair short to ground in appropriate Dark Green/Violet wire circuit. Retest system.
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