A/C COMPRESSOR HI TEMP CUTOUT SYSTEM OPERATION

FIRENZA MODELS EQUIPPED WITH AIR CONDITIONING AND AUTOMATIC TRANSMISSION HAVE A SYSTEM WHICH PREVENTS A/C COMPRESSOR OPERATION IF THE ENGINE BEGINS TO OVERHEAT. A COOLANT TEMPERATURE SWITCH SENSES COOLANT TEMPERATURE AND CLOSES WHEN COOLANT REACHES 258 DEGREES. THE CLOSING OF THE SWITCH SUPPLIES GROUND FOR THE WIDE OPEN THROTTLE RELAY . THIS RELAY OPENS THE COMPRESSOR CLUTCH CIRCUIT, PREVENTING COMPRESSOR OPERATION. THE WIRING FOR THIS CIRCUIT IS SHOWN ON PAGE 8A-79 OF THE 1982 FIRENZA SERVICE MANUAL. HOWEVER, THIS PAGE ONLY SHOWS THE SYSTEM FOR CARS WITHOUT GAGES. MODELS EQUIPPED WITH GAGES WILL BE WIRED SLIGHTLY DIFFERENT. ON MODELS WITH GAGES, A SINGLE BRN (BROWN) WIRE WILL RUN FROM SPLICE S119 (LOCATED IN ENGINE HARNESS, NEXT TO RELAY BRACKET) DIRECTLY TO THE COOLANT TEMPERATURE SWITCH. THE LOCATION OF THIS SWITCH IS SHOWN IN FIG. 2. THE TEMPERATURE SWITCH LEAD BREAKS-OUT OF THE ENGINE HARNESS AT THE SAME POINT THAT THE ELECTRIC CHOKE AND EFE HEATER LEADS BREAK OUT OF THE HARNESS (SEE ENGINE VIEWS ON PAGE 6D-38 OF THE FIRENZA SERVICE MANUAL FOR LOCATION). THE SWITCH LEAD IS TAPED TO THE EFE HEATER LEAD AND ROUTES OVER THE VALVE COVER, ALONG SIDE OF THE CARBURETOR AND DOWN TO THE SWITCH. NOTE THESE CHANGES IN YOUR SERVICE MANUAL.

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.