LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Buick >> 2001 >> Century Custom >> Repair and Diagnosis >> Body & Frame >> Windows >> Power Window System >> System Tests >> Test A: All Power Windows Inoperative
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Test A: All Power Windows Inoperative

NOTE: Reviewing system description and operation information will help determine if condition described by customer is normal operation, and may help determine correct symptom diagnostic procedure when a malfunction exists.
  1. If power window system description and operation has been reviewed, go to next step. If description and operation has not been reviewed, see POWER WINDOW SYSTEM  under DESCRIPTION & OPERATION.
  2. Attempt to operate all power windows. If all power windows do not operate properly, go to next step. If all power windows operate properly, go to DIAGNOSING INTERMITTENTS  .
    3. NOTE: Driver door window switch may be referred to as left front window switch, master window switch or master switch.
  3. Disconnect master switch harness connectors. Turn ignition switch to RUN position. Connect a test light between ground and master switch C1 7-pin harness connector terminal "G" (Yellow wire). See Fig 1 . If test light illuminates, go to next step. If test light does not illuminate, go to step  5 .
  4. Connect test light between master switch C1 7-pin harness connector terminal "B" (Black wire) and terminal "G" (Yellow wire). If test light illuminates, go to step  6 . If test light does not illuminate, go to step  7 .
  5. Test Yellow wire between instrument panel fuse block and master switch C1 7-pin harness connector for an open or short to ground. See WIRING DIAGRAMS  . If an open or short to ground is not found, attempt to diagnose Retained Accessory Power (RAP) system by symptom. See TEST C: RETAINED ACCESSORY POWER INOPERATIVE or TEST D: RETAINED ACCESSORY POWER ON AFTER TIME-OUT in appropriate BODY CONTROL MODULES article. If an open or short to ground is found, repair as necessary. After repair, go to step  9 .
  6. Check for poor connections at master switch connectors. If poor connections are not found, go to step  8 . If poor connections are found, repair as necessary. After repair, go to step  9 .
  7. Repair open in Black wire between master switch C1 7-pin connector and ground point. See WIRING DIAGRAMS  . Ground point is located inside left door sill, forward of front seat. After repair, go to next step. 9 .
  8. Replace master switch. See WINDOW SWITCH  under REMOVAL & INSTALLATION. After repair, go to next step.
  9. Operate system to verify repairs. If system does not operate properly, go to step  2 . If system operates properly, system is okay.
Fig 1: Identifying Power Window Switches Harness Connectors & Terminals
G00007269Courtesy of GENERAL MOTORS CORP.
scientia non olet · About LEMON Manuals