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Test C: One-Touch Down Inoperative

NOTE: After making any repair, repeat Generic Electronic Module (GEM) self-test using NGS tester.
NOTE: If DTCs B1302, B1304, or B1359 are present, repair these codes before proceeding. See GENERIC ELECTRONIC MODULE DTC INDEX  table under SELF-DIAGNOSTIC SYSTEM. For complete DTC listing, see MODULE COMMUNICATIONS NETWORK - SABLE & TAURUS article.
  1. Using New Generation Star (NGS) tester, perform Generic Electronic Module (GEM) self-test. If no DTCs are present, go to next step. If DTC B1398 is present, go to step  7 . If DTC B1400 is present, go to step  3 . If DTC B1405 is present, go to step  9 .
  2. Turn ignition switch to ON position. Monitor GEM PID D_PWRLY while pressing driver's window control switch. If PID D_PWRLY indicates off -B-, go to next step. If GEM PID D_PWRLY does not indicate off -B-, go to step  7 .
  3. Turn ignition switch to OFF position. Disconnect One-Touch Down (OTD) relay from connector C2051 located on instrument panel fuse box. See Figure . Turn ignition switch to ON position. Measure voltage between OTD relay connector C2051 terminal No. 1 and ground. See Figure . If any voltage is present, go to next step. If no voltage is present, go to step  5 .
  4. Turn ignition switch to OFF position. Disconnect GEM harness connector C201d. Turn ignition switch to ON position. Measure voltage between OTD relay connector C2051 terminal No. 1 and ground. If any voltage is present, repair instrument panel fuse box as necessary. If no voltage is present, go to step  17 .
  5. Turn ignition switch to OFF position. Disconnect delayed accessory relay located on instrument panel fuse box. Turn ignition switch to ON position. Measure voltage between OTD relay connector C2051 terminal No. 2 and ground. If any voltage is present, go to next step. If no voltage is present, go to step  7 .
  6. Turn ignition switch to OFF position. Disconnect instrument panel fuse box connector C270c. Turn ignition switch to ON position. Measure voltage between OTD relay connector C2051 terminal No. 2 and ground. If any voltage is present, repair instrument panel fuse box as necessary and retest system operation. If no voltage is present, repair Light Blue/Black wire. See WIRING DIAGRAMS in POWER DOOR LOCKS article. Retest system operation.
  7. Turn ignition switch to OFF position. Reconnect delayed accessory relay. Turn ignition switch to ON position. Using New Generation Star (NGS) tester, select GEM active command ONE TOUCH WINDOW DOWN & ACC DELAY. Trigger ACCY RLY to ON position. Trigger ONE TOUCH to ON position. If window does not cycle down, go to next step. If window cycles down, go to step  17 .
  8. Turn ignition switch to ON position. Disconnect OTD relay from connector C2051 on instrument panel fuse box. Select GEM active command ONE TOUCH WINDOW DOWN & ACCY DELAY. Trigger ACCY RLY to ON position. Measure voltage between OTD relay connector C2051 terminal No. 5 and ground. If voltage is greater than 10 volts, go to next step. If voltage is less than 10 volts, repair instrument panel fuse box as necessary and retest system operation.
  9. Turn ignition switch to OFF position. Disconnect driver's window control switch harness connector C504a. Turn ignition switch to ON position. Measure voltage between driver's window control switch harness connector C504a terminal No. 8 (Gray/Light Blue) wire and ground. See Figure . If any voltage is present, go to next step. If no voltage is present, go to step  11 .
  10. Turn ignition switch to OFF position. Disconnect GEM harness connector C201c. Turn ignition switch to ON position. Measure voltage between driver's window control switch harness connector C504a terminal No. 8 (Gray/Light Blue wire) and ground. If any voltage is present, repair short to power in Gray/Light Blue wire. If no voltage is present, go to step  17 .
  11. Turn ignition switch to OFF position. Disconnect driver's window control switch harness connectors C504a and C504b. Test master window control switch. See MASTER WINDOW CONTROL SWITCH  under COMPONENT TESTS. If switch tests okay, go to next step. If switch fails test, replace driver's window control switch and retest system operation.
  12. Measure resistance between master window control switch harness connector C504a terminal No. 8 (Gray/Light Blue wire) and ground. If resistance is less than 10 k/ohms, go to next step. If resistance is greater than 10 k/ohms, go to step  14 .
  13. Disconnect GEM harness connector C201c. Measure resistance between master window control switch harness connector C504a terminal No. 8 (Gray/Light Blue wire) and ground. If resistance is greater than 10 k/ohms, go to step  17 . If resistance is less than 10 k/ohms, repair short to ground in Gray/Light Blue wire and retest system operation.
  14. With GEM harness connector C201c disconnected, measure resistance between master window control switch harness connector C504a terminal No. 8 (Gray/Light Blue wire) and GEM harness connector C201c terminal No. 15. See Fig 1 . If resistance is less than 5 ohms, go to next step. If resistance is greater than 5 ohms, repair open in Gray/Light Blue wire and retest system operation.
  15. Disconnect GEM harness connector C201d. Disconnect OTD relay from connector C2051 located on instrument panel fuse box. Measure resistance between GEM harness connector C201d terminal No. 12 and OTD relay connector C2051 terminal No. 1. See Figure and Figure . If resistance is less than 5 ohms, go to next step. If resistance is greater than 5 ohms, repair open in instrument panel fuse box as necessary.
  16. Disconnect instrument panel fuse box connector C270c. Measure resistance between instrument panel fuse box connector C270c terminal No. 6 and GEM harness connector C201d terminal No. 13. See Figure . Measure resistance between instrument panel fuse box connector C270c terminal No. 6 and GEM harness connector C201d terminal No. 24. If resistances are less than 5 ohms, go to next step. If any resistance is greater than 5 ohms, repair instrument panel fuse box as necessary and retest system operation.
  17. Visually inspect GEM for corroded or pushed-out terminals. Inspect GEM harness connector for correct seating. Connect any disconnected connectors and ensure all connectors are fully seated. Operate the system and verify customer complaint is still present. If concern is still present, replace GEM. If concern is no longer present, system is operating properly at this time. Customer concern may have been caused by loose or corroded connector.
Fig 1: Identifying GEM Harness Connector C201c Terminals
G00012287Courtesy of FORD MOTOR CO.
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