INFO. - DIAG PROC. WHEN A/C DIAG INFO LEAK. GMC Truck GMC C Pickup

REVISION: 01/14/98

THIS BULLETIN IS BEING REVISED TO INCLUDE AN ATTACHMENT THAT WAS INADVERTANTLY OMITTED FROM THIS BULLETIN. PLEASE DISCARD COPRORATE BULLETIN NUMBER 73-12-12 (1 - HVAC). ______________________________________________________________________

SUBJECT: INFORMATION - DIAGNOSTIC PROCEDURE WHEN A/C REFRIGERANT LEAK CANNOT BE FOUND

MODELS: 1997-98 PASSENGER CARS AND LIGHT DUTY TRUCKS

THE FOLLOWING DIAGNOSTIC PROCEDURE SHOULD BE USED WHEN AN A/C REFRIGERANT LEAK CANNOT BE FOUND WHEN USING A LEAK DETECTOR, J 39400-A.

1. MAKE A COPY OF ATTACHMENT 1 (SERVICE INFORMATION FORM).

2. USING AN ACR4 RECOVER/RECHARGE STATION J39500-B, RECORD THE NECESSARY INFORMATION.

3. RECOVER THE EXISTING R134A REFRIGERANT AND RECORD REFRIGERANT WEIGHT.

4. ADD R134A FLORESCENT DYE J 41447 OR GM P/N 12346303, USING THE DYE INJECTOR J 41459.

5. RE-CHARGE THE SYSTEM FOLLOWING THE PROCEDURES IN SECTION 1B OF THE SERVICE MANUAL.

6. CHECK THE SYSTEM FOR LEAKS USING A HIGH INTENSITY BLACK LIGHT J 42220 OR GM P/N 12377979.

IMPORTANT:

R134A FLORESCENT DYE WILL REMAIN IN THE LUBRICANT FOR THE LIFE OF THE VEHICLE AS LONG AS THE VEHICLE'S A/C SYSTEM HAS NOT BEEN FLUSHED.

IF NO LEAKS CAN BE FOUND, RETURN THE VEHICLE TO THE CUSTOMER AND ADVISE THEM OF THE DYE IN THE SYSTEM AND THAT IT MAY NEED TO BE RECHECKED AT A LATER DATE. ATTACH THE SERVICE INFORMATION FORM TO THE WARRANTY REPAIR ORDER WHEN COMPLETED.

PARTS INFORMATION:

PARTS ARE CURRENTLY AVAILABLE FROM GMSPO.

WARRANTY INFORMATION:

IMPORTANT:

THIS BULLETIN ADDRESSES AN A/C REFRIGERANT LEAK THAT CANNOT BE FOUND ON VEHICLES. THIS LABOR CODE CAN ONLY BE USED WITHIN 12 MONTHS DATE OF PURCHASE AND A MAXIMUM 1 LB R134A REFRIGERANT CAN BE CHARGED TO THE WARRANTY REPAIR ORDER.

FOR VEHICLES REPAIRED UNDER WARRANTY, USE:

LABOR OPERATION LABOR OPERATION NUMBER DESCRIPTION TIME --------------- ----------- ---------------

D4450 A/C SYSTEM - LEAK TEST 0.8 HR DYE DIAGNOSIS

FIGURES: 00 ATTACHMENTS: 01

Object Number: 335440 Size: FS

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.