COOLANT FAN SYSTEM DIAGNOSTICS SHOP MANUAL REVISION

MODEL AND YEAR: 1986 CELEBRITY WITH 3.8L V-6 MFI ENGINE (VIN CODE W)

The 1986 Celebrity Service Manual 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 coolant fan control system used in the 2.8L V6 MFI engine (VIN W).

When diagnosing a customer comment of the cooling fan running whenever the ignition switch is in run, please note the A/C high pressure switch is a normally CLOSED switch. The 1986 Celebrity Service Manual incorrectly indicates that the A/C high pressure switch is a normally open switch.

The schematic contained in this bulletin should be used when performing coolant fan system diagnostics, it correctly indicates that the A/C high pressure switch is a normally closed switch which opens at 1930 kpa (280 psi).

NOTICE: CORRECT THE COOLANT FAN SCHEMATIC ON PAGE 8A-31-4 OF THE 1986 CELEBRITY SERVICE MANUAL TO AGREE WITH THE SCHEMATIC CONTAINED IN THIS BULLETIN.

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.