GM Service Manual Online
For 1990-2009 cars only

INFO. ON FALSE CLASS 2 SERIAL DATA DIAGNOSTIC TROUBLE CODES

SUBJECT: INFORMATION ON FALSE CLASS 2 SERIAL DATA DIAGNOSTIC TROUBLE CODES (DTCS) SET BY THE A/C PROGRAMMER

MODELS: 1996 CADILLAC CONCOURS, DEVILLE, ELDORADO, SEVILLE

SOME OF THE ABOVE LISTED VEHICLES MAY EXPERIENCE THE SETTING OF FALSE CLASS 2 SERIAL DATA DIAGNOSTIC TROUBLE CODES (DTCS) BEING SET BY THE A/C PROGRAMMER (ACM). A FALSE CLASS 2 SERIAL DATA CODE IS A FOUR DIGIT CODE THAT BEGINS WITH THE NUMBER 2. THIS CAN BE ANY DTC OTHER THAN 2016, 2064, 2096, 2153 AND 2255.

THESE DTCS WILL NOT TURN ON THE MIL LAMP OR DISPLAY A MESSAGE ON THE DRIVER INFORMATION CENTER (DIC). THESE FALSE DTCS ARE DISCOVERED WHEN THE SERVICE TECHNICIAN ENTERS ON-BOARD DIAGNOSTICS AND VIEWS ACM DTCS. THE SETTING OF THESE FALSE CODES WILL NOT AFFECT ANY OPERATION OF THE VEHICLE. THE FALSE DTC IS CLEARED WHEN THE BATTERY IS MOMENTARILY DISCONNECTED. THESE DTCS WILL NOT RETURN AFTER THE CODE HAS BEEN CLEARED BY A BATTERY DISCONNECT.

FIGURES: 00 ATTACHMENTS: 00

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.

COPYRIGHT 1996 GENERAL MOTORS CORPORATION. ALL RIGHTS RESERVED.