Customers transferring the Cadillac factory garage door opener from a 1988 Cadillac to a 1989 or 1990 DeVille or Fleetwood with heated windshield may experience reduced garage door opener operating range. The range may be reduced by up to 50%.
Reduced range on the Electriclear equipped cars is caused by the transparent metallic heating film between the layers of the windshield glass. The garage door opener transmitter signal is weakened as it passes through the metal heating film.
Customers may wish to refer to the 1989 or 1990 DeVille/Fleetwood Owner's Manual, under "Garage Door Opener (Option)" and also under "Heated Windshield (Option)", for commentary on heated windshield and its effects on garage door openers, radar detectors, and other radio receivers/transmitters using signals which pass through the windshield.
To improve the garage door opener range, have the customer check receiver mounting location. For best results the receiver should be mounted so that the antenna has minimal interference from metal objects between the car and the receiver antenna. Some receivers which were mounted behind metal garage doors or in the back of the garage may have to be moved. It may help to extend the small metal receiver antenna by attaching a length of wire.
In a worst case (poor receiver mounting location, heated windshield, and/or local radio frequency interference) the customer may have to operate the garage door opener using the provided battery pack. Using the transmitter plugged into the battery pack and clipped onto the sun visor or to the existing garage door opener receptacle will improve the opener operating range.
In the event that the garage door opener still does not operate with the car very close to the receiver, refer to Section 9F of the 1989 DeVille/Fleetwood Service Information Manual, Miscellaneous Accessories - Garage Door Opener. If Section 9F of the Service Information Manual is unable to locate the problem, return the transmitter and receiver to Prince Corporation for alignment. Refer to Section 9F of the 1989 DeVille/Fleetwood Service Information Manual for the address.
For warranty purposes use Labor Operation R4650 Garage Door Opener Transmitter-Replace at .2 hour, R4651 Garage Door Opener Receiver Replace at .2 hour.
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.