COOLANT FAN SYSTEM DIAGNOSTICS SHOP MANUAL REVISION

MODELS AFFECTED: 1985-1987 CIMARRONS EQUIPPED VvTrH 2.8L ENGINE

Some 1985-1987 Cimarrons equipped with the 2.8L V-6 engine may experience a condition of the cooling fan running when the ignition switch is in the run position with or without the engine running. This may be due to an open in one of the following circuits and/or an open in the A/C cooling fan pressure switch.

1985 - circuit 257 and/or 450 1986 - circuit 257 and/or 450 1987 - circuit 603 and/or 150

The 1985 through 1987 Cimarron Service Information Manuals may lead to unnecessary replacement of the air condition high pressure switch or Electronic Control Module (ECM) as a result of inaccurate information on the cooling fan control system.

IMPORTANT: The A/C high pressure switch is a NORMALLY CLOSED SWrrCH. The high pressure switch will open at 1930 kpa (280 psi). Therefore:

Cooling fan on - switch is open Cooling fan off - switch is closed

IMPORTANT: The cooling fan schematic on the following Service Manual pages should be corrected to reflect the air conditioning high pressure switch as a normally closed switch.

Year Service Information Manual Page ------------------ ---- 1985 8A-58 1986 8A-31-0 1987 8A-31-0

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.