POWER WINDOWS INOP INTERMITT. REPLACE POWER WINDOW SWITCH

SUBJECT: INTERMITTENT OPERATION OF POWER WINDOWS (REPLACE SWITCH)

VEHICLES AFFECTED: 1990-91 CHEVROLET LUMINA APV AND PONTIAC TRANSPORT

Condition:

--------- The power windows may operate intermittently on the 1990-91 U-van. The windows may roll down properly, then roll up one or two inches. After waiting a few seconds, the switch can again be used to raise the windows either partially or all the way up.

Cause:

----- The driver's side power window switch may stick in the down position, causing the motor to overload, tripping the internal circuit breaker in the motor. As the motor cools, the window can be operated again. Prolonged use of the windows with this condition may shorten the life of the motor.

Correction:

---------- The 1992 U-van uses a new design power window switch which does not have this condition. All service stock has been replaced with the new switch.

The 1992 switch design operates differently than the 1990-91 switch, and has a different feel. Refer to Product Service Bulletin 92-8-134 for detailed information. Remember to inform the customer of the differences in the new switch.

Because of the intermittent nature of this condition, normal diagnosis may lead to replacement of the motor. If this condition is found, the driver's side power window switch should be replaced, following the procedure in Section 10-6 of the Service Manual.

General Motors bulletins are intended for use by professional technicians, not a "do-it-yourselfer". They are written to inform those technicians of conditions that may occur on some vehicles, or to provide information that could assist in the proper service of a vehicle. Properly trained technicians have the equipment, tools, safety instructions and know-how to do a job properly and safely. If a condition is described, do not assume that the bulletin applies to your vehicle, or that your vehicle will have that condition. See a General Motors dealer servicing your brand of General Motors vehicle for information on whether your vehicle may benefit from the information.