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Test D: Driver's Power Window Inoperative (Convertible)

  1. 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, to right of steering column. Turn ignition switch to RUN position. Using NGS tester, monitor Generic Electronic Module (GEM) PID IGN_A, IGN_R, IGN_S and IGN_KEY. Insert key into ignition switch and turn ignition switch to each position while observing PIDs. If PIDs agree with ignition switch positions, go to next step. If PIDs do not agree with ignition switch positions, repair ignition switch concern. See STEERING COLUMN SWITCHES - MUSTANG article.
  2. Turn ignition switch to RUN position. Using NGS tester, monitor GEM PID D_UP_SW and D_DN_SW while operating master window/door lock switch to driver's window up and down positions. If PIDs do not agree with switch positions, go to next step. If PIDs agree with switch positions, go to step  9 .
  3. Turn ignition switch to LOCK position. Disconnect master window/door lock switch harness connector C505. Turn ignition switch to RUN position. Measure voltage between ground and master window/door lock switch harness connector C505 terminal No. 15 (Light Blue/Black wire). See Figure . If battery voltage exists, go to next step. If battery voltage does not exist, go to step  8 .
  4. Turn ignition switch to LOCK position. Measure resistance between ground and master window/door lock switch harness connector C505 terminal No. 14 (Black wire). If resistance is 5 ohms or less, go to next step. If resistance is more than 5 ohms, repair open in Black wire between master window/door lock switch and ground. Ground point is located in left rear of vehicle. See WIRING DIAGRAMS  .
  5. Test master window/door lock switch. See MASTER WINDOW/DOOR LOCK SWITCH  under COMPONENT TESTS. If switch is okay, go to next step. If switch is defective, replace master window/door lock switch.
  6. Disconnect 4-pin Generic Electronic Module (GEM) harness connector C290. GEM is located behind left side of instrument panel, next to central junction box. Measure voltage between ground and GEM harness connector C290 terminal No. 1 (White/Black wire) with ignition switch in LOCK and RUN positions. See Figure . If battery voltage does not exist with ignition switch in either position, go to next step. If battery voltage exists with ignition switch in either position, repair short to voltage in White/Black wire between GEM and driver's power window motor. See WIRING DIAGRAMS  .
  7. Turn ignition switch to LOCK position. Disconnect 20-pin GEM harness connector C292. Measure resistance in Tan/Light Blue wire between GEM harness connector C290 terminal No. 4 and master window/door lock switch harness connector C505 terminal No. 8. See Figure and Figure . Also measure resistance in White/Black wire between GEM harness connector C292 terminal No. 14 and master window/door lock switch harness connector C505 terminal No. 6. See Fig 1 . If both resistance readings are 5 ohms or less, replace GEM. See REMOVAL & INSTALLATION  . If either resistance reading is more than 5 ohms, repair open in appropriate wire between GEM and master window/door lock switch. See WIRING DIAGRAMS  .
  8. Turn ignition switch to LOCK position. Remove circuit breaker No. 43 (20-amp) from Central Junction Box (CJB). CJB is located behind left side of instrument panel, left of steering column. Measure resistance in Light Blue/Black wire between output side of circuit breaker No. 43 and master window/door lock switch harness connector C505 terminal No. 15. If resistance is 5 ohms or less, repair or replace CJB as necessary. If resistance is more than 5 ohms, repair open in Light Blue/Black wire between master window/door lock switch and CJB. See WIRING DIAGRAMS  .
  9. Using NGS tester, access GEM active command FRONT WINDOW CONTROL. Trigger DR DOWN on. If driver's window does not go down, go to next step. If driver's window goes down, replace GEM. See REMOVAL & INSTALLATION  .
  10. Turn ignition switch to LOCK position. Disconnect driver's window motor harness connector C504. Using fused jumper wires, apply battery voltage to one terminal at driver's window motor connector and momentarily ground other terminal (component side). To reverse motor direction, reverse polarity of jumper wires. If window operates in both directions, go to next step. If window does not operate in both directions, repair binding linkage and/or replace window motor as necessary. See REMOVAL & INSTALLATION  .
  11. Disconnect master window/door lock switch harness connector C505. Measure resistance in White/Black wire between driver's window motor harness connector C504 and master window/door lock switch harness connector C505 terminal No. 6. See Figure . If resistance is 5 ohms or less, go to next step. If resistance is more than 5 ohms, repair open in White/Black wire between driver's window motor and master window/door lock switch. See WIRING DIAGRAMS  .
  12. Disconnect 4-pin Generic Electronic Module (GEM) harness connector C290. GEM is located behind left side of instrument panel, next to Central Junction Box (CJB). Measure resistance in White/Black wire between driver's window motor harness connector C504 and GEM harness connector C290 terminal No. 1. See Figure . If resistance is 5 ohms or less, go to next step. If resistance is more than 5 ohms, repair open in White/Black wire between driver's window motor and GEM. See WIRING DIAGRAMS  .
  13. Remove circuit breaker No. 43 (20-amp) from CJB. CJB is located behind left side of instrument panel, left of steering column. Measure resistance in Light Blue/Black wire between output side of circuit breaker No. 43 and GEM harness connector C290 terminal No. 4. If resistance is 5 ohms or less, replace GEM. See REMOVAL & INSTALLATION  . If resistance is more than 5 ohms, repair open in Light Blue/Black wire between GEM and circuit breaker No. 43. See POWER DISTRIBUTION article in WIRING DIAGRAMS.
Fig 1: Identifying Generic Electronic Module Harness Connector C292 Terminals
G99E02708Courtesy of FORD MOTOR CO.