For 1990-2009 cars

# SERVICE MANUAL UPDATE-SEC.1B REVISED A/C DIAGNOSTIC CHARTS

#### MODELS AFFECTED: 1989 SKYHAWK 1989 - 1990 SKYLARK

The following changes should be made in the "Air Conditioning" section 1B, within the diagnostic charts entitled "V-5 System Air Conditioning Diagnosis Insufficient Cooling."

Starting on page: 1B-12 for 1989 Skyhawk and Skylark 1B-13 for 1990 Skylark

On the second page of step 4 under the pressure graph there are four boxes containing information.

The small box on the left should contain the following information:

Low and high side pressures intersect in the black area of the chart. DO STEP 6.

The small box on the right should contain the following information:

Low and high side pressures intersect in the gray area of the chart. DO STEP 5.

Also the pages/steps following this correction should read:

"Step 5 - GREY zone performance checks" "Step 6 - BLACK zone performance checks"

Be sure to mark these corrections in your service manuals for future reference.

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.