1998 Oldsmobile RegencyFACTORY OEM SERVICE PROCEDURE

Left Front Window Does Not Operate

  1. Disconnect express down module connector, located at front of left front door. Turn ignition switch to RUN position. Connect test light between ground and express down module connector terminal "A" (Brown wire). If test light illuminates, go to next step. If test light does not illuminate, repair open in circuit No. 141 (Brown wire) between power window 25-amp circuit breaker and express down module.
  2. Connect test light between express down module connector terminals "B" (Gray wire) and "C" (Dark Blue wire). Press left front window switch to UP and DOWN positions. If test light illuminates in both switch positions, go to next step. If test light does not illuminate in both switch positions, check circuits No. 1136 (Gray wire) and No. 164 (Dark Blue wire) between express down module and master switch. If circuits and connector contact is okay, replace master window switch.
  3. Disconnect left front window motor connector. Connect test light between ground and left front window motor connector terminal "B" (Dark Blue wire). Press left front window switch at master window switch to UP position. If test light illuminates, go to next step. If test light does not illuminate, repair open in circuit No. 164 (Dark Blue wire) between left front window motor and splice S500.
  4. Reconnect left front window motor connector. Connect a fused jumper between express down module connector terminals "A" (Brown wire) and "D" (Brown wire). If left front window motor operates, go to next step. If left front window motor does not operate, repair open in circuit No. 165 (Brown wire) between express down module and left front window motor. If wire and connector contact at left front motor are okay, replace motor.
  5. Connect a fused jumper between ground and express down module harness connector terminal "D" (Brown wire). Press left front window switch on master window switch to UP position. If left front window motor does not operate, check for proper terminal contact at left front window motor. If terminal contact is okay, replace motor. If left front window motor operates, check express down module harness connector for poor terminal contact. If okay, replace express down module.
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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • • You smell fuel, burning insulation, or see smoke.
  • • Brakes feel soft, pull hard to one side, or make grinding noises.
  • • The engine overheats, stalls repeatedly, or misfires under load.
  • • You are missing required tools, torque specs, or safe lifting equipment.
  • • You are not confident in the next step or safety outcome.

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