INFO - DIAG. HINTS FOR 'ROLLING CODE' REMOTE FUNC.

SUBJECT: INFORMATION - DIAGNOSTIC HINTS FOR "ROLLING CODE" REMOTE FUNCTION ACTUATION (RFA) SYSTEMS

MODELS: 1996 BUICK LESABRE, PARK AVENUE, RIVIERA 1996 CADILLAC DEVILLE, ELDORADO, SEVILLE 1998 CADILLAC CATERA 1996 CHEVROLET CAMARO 1996 OLDSMOBILE AURORA, EIGHTY EIGHT, LSS, REGENCY 1996 PONTIAC BONNEVILLE, FIREBIRD

1997-98 PASSENGER CARS EXCEPT CORVETTE AND GEO

1997-98 TRUCK MODELS EXCEPT GEO TRACKER

MOST GM VEHICLES, AS LISTED ABOVE, NOW USE REMOTE FUNCTION ACTUATION (FORMERLY CALLED REMOTE KEYLESS ENTRY) SYSTEMS WITH A "ROLLING CODE" SECURITY SYSTEM. THESE SYSTEMS CAN BE IDENTIFIED BY A TEAR DROP SHAPED TRANSMITTER (FOB). OLDER RKE SYSTEMS USE A RECTANGULAR TRANSMITTER.

"ROLLING CODE" TECHNOLOGY OFFERS A NEW LEVEL OF SECURITY FOR THE RFA SYSTEM THAT WAS NOT AVAILABLE IN EARLIER VEHICLES. THIS NEW LEVEL OF SECURITY PREVENTS ANYONE FROM RECORDING THE MESSAGE BEING SENT FROM THE TRANSMITTER TO THE RECEIVER AND PLAYING IT BACK AGAIN TO GAIN ENTRY TO A VEHICLE.

"ROLLING CODE" REFERS TO THE WAY THE INFORMATION IS BEING SENT OUT BY THE RFA TRANSMITTER AND ACCEPTED BY THE RECEIVER. THE TRANSMITTED SIGNAL IS SCRAMBLED IN A DIFFERENT ORDER UPON RFA TRANSMISSION. THE TRANSMITTER AND RECEIVER KEEP TRACK OF THE APPROPRIATE ORDER OF THE TRANSMITTED INFORMATION. WHEN THE SIGNAL BEING SENT BY THE TRANSMITTER IS NOT IN THE ORDER THAT THE RECEIVER IS EXPECTING, THE TRANSMISSION IS DEEMED INVALID AND NO OPERATION IS PERFORMED. THIS OCCURS WHEN THE RECEIVER AND TRANSMITTER ARE "OUT OF SYNCHRONIZATION".

THE NEW "ROLLING CODE" SECURITY SYSTEM INTRODUCES A DIAGNOSTIC PROCEDURE THAT IS DIFFERENT FROM THE PREVIOUS KEYLESS ENTRY SYSTEM. TO DIAGNOSE THE RFA SYSTEM, REFER TO SECTION 9K IN THE APPROPRIATE SERVICE MANUAL. LISTED BELOW ARE SEVERAL PRELIMINARY STEPS TO SIMPLIFY DIAGNOSIS.

1. FIRST, TRY TO RESYNCHRONIZE THE SYSTEM BY PRESSING THE "UNLOCK" AND "LOCK" BUTTONS TOGETHER WITHIN RANGE OF THE VEHICLE FOR APPROXIMATELY 7 SECONDS. THERE SHOULD BE SOME FEEDBACK FROM THE VEHICLE THAT THE SYSTEM HAS BEEN SYNCHRONIZED (HORN HONKS, LOCKS CYCLE, LIGHTS FLASH, ETC).

ON 1996-97 CADILLAC MODELS (EXCEPT CATERA), AND ON THE 1998 CATERA, USE THE "TRUNK" AND "LOCK" BUTTONS TO RESYNCHRONIZE. THERE WILL BE NO FEEDBACK FROM THE SYSTEM.

2. CONFIRM THE POLARITY AND CONDITION OF THE TRANSMITTER BATTERY (I.E., REPLACE WITH A FRESH BATTERY). SEE FIGURE 1. THE BATTERY SHOULD BE INSTALLED WITH THE "+" SIDE DOWN (NOT SHOWING".

ALSO, INSURE THAT THE CIRCUIT BOARD IS INSTALLED CORRECTLY. SEE FIGURE 2. THE CIRCUIT BOARD SHOULD BE INSTALLED WITH THE PARTS FACING OUT.

3. REPROGRAM THE SYSTEM. BE SURE TO HAVE ALL TRANSMITTERS FROM THE CUSTOMER PRIOR TO REPROGRAMMING. REFER TO THE APPROPRIATE SERVICE MANUAL FOR PROGRAMMING PROCEDURES.

4. MAKE SURE TO USE THE CORRECT TRANSMITTER FOR THE VEHICLE. ALL FOBS MIGHT LOOK ALIKE, BUT THERE ARE EIGHT DIFFERENT SYSTEMS FROM THREE SUPPLIERS THAT ARE NOT INTERCHANGEABLE WITH EACH OTHER. USE THE CORRECT PART NUMBER FROM THE GMSPO PARTS BOOK.

ALSO REFERENCE CORPORATE SERVICE BULLETINS #63-90-10, #63-90-11, AND #73-90-13 FOR MORE SPECIFIC INFORMATION ON CERTAIN CARLINES.

FIGURES: 02 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 1997 GENERAL MOTORS CORPORATION. ALL RIGHTS RESERVED.