GM Service Manual Online
For 1990-2009 cars only

HIGH BLOWER OPERATES WITH IGNITION KEY OFF

UNWANTED HIGH BLOWER OPERATION WITH IGNITION KEY OFF

Vehicles Affected: 1982-1988 CIMARRON -----------------

Some 1982-1988 Cimarrons may experience high blower operation with key off. This condition may be caused by a back feed voltage induced on circuit 50, which powers the "blower off". This back feed voltage could be due to a failed diode in the generator rectifier bridge.

To verify that the blower is being commanded on by this type of back feed, disconnect circuit 25 (on 1982-1986 vehicles) or circuit 250 (on 1987-1988 vehicles), the brown field wire, from the generator. If all unwanted blower operation discontinues with the ignition key off, for vehicles with serviceable generators, remove the generator and test the rectifier bridge as outlined in Section 6D of the Cimarron Service Information Manual under Generator Disassembly, Test, and Reassembly. For vehicles with non-serviceable generators, replace the generator.

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.