GM Service Manual Online
For 1990-2009 cars only

ELECT CLIMATE CONTROL TOO WARM REPLACE BCM PROM

SUBJECT: ELECTRONIC CLIMATE CONTROL (ECC) TOO WARM IN HEAT MODE

MODELS AFFECTED: 1992 DE VILLES AND FLEETWOODS (VIN BREAKPOINT N4257163)

Some 1992 DeVilles and Fleetwoods may control too warm when operating in heat mode. This may be due to an incorrect calibration within the BCM PROM.

IMPORTANT- Vehicles prior to VIN breakpoint N4257163 with this concern should perform Service Bulletin T-92-30A (for cool air from defrost and side window defog outlets and imbalanced duct temperature from right to left in heat). Replacing PROM with newly calibrated PROM without changing the air distribution baffles within the HVAC module could enhance a temperature variation concern.

To correct this concern replace the BCM PROM with the part listed below:

PROM Broadcast I.D. Code P/N ---- --------- ---- 68 BCRS 16183880

For more information on PROM replacement procedure refer to the Service Information Manual, Section 8C.

Parts are currently available from GMSPO.

For warranty purposes use Labor Operation N4801 at .6 hour.

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.