For 1990-2009 cars

# UNWANTED BLOWER OPERATION OR IMPROPER AIR DELIVERY ECC

#### SUBJECT: UNWANTED BLOWER OPERATION OR IMPROPER AIR DELIVERY FROM ELECTRONIC CLIMATE CONTROL (ECC)

#### VEHICLES AFFECTED: 1986-91 E AND K MODELS

1986-1991 Eldorados and Sevilles are equipped with a BCM controlled Electronic Climate Control (ECC) system that will, under certain conditions, operate the blower with the ECC in the "OFF" position or direct air delivery to the A/C vents with the ECC in Front Defrost mode.

The ECC system is programmed with a mode called Instrument Panel Cluster (IPC) Cooling. The purpose of this mode is to prevent the IPC from overheating under high ambient temperature conditions. The ECC system will enter this mode if all of the following conditions are met:

- The ignition is in the run position.

- The in-car temperature is greater than 34 C (93 F) or the sun load temperature is greater than 410C (105 F),

- The engine is not running or the HVAC is in the off setting or the is in the Front Defrost setting.

When the ECC system enters the IPC Cooling Mode, the blower will operate at a medium speed and the ECC will deliver air through the A/C vents. This mode will not affect compressor operation.

This condition is normal. No attempt should be made to repair a vehicle with this condition.

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.