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MALFUNCTION INDICATOR LAMP (MIL) ILLUMINATED

SUBJECT: MALFUNCTION INDICATOR LAMP (MIL) ILLUMINATED; DIAGNOSTIC TROUBLE CODE (DTC) P0121 STORED (FLASH WITH NEW CALIBRATION DO NOT REPLACE ANY COMPONENTS)

MODELS: 1997 BUICK LESABRE, RIVIERA 1997 OLDSMOBILE 88, LSS, REGENCY 1997 PONTIAC BONNEVILLE, GRAND PRIX WITH 3800 SERIES II (VIN K - RPO L36)

CONDITION:

SOME 1997 VEHICLES BUILT PRIOR TO SEPTEMBER 15, 1996 MAY ILLUMINATE THE MALFUNCTION INDICATOR LAMP AND STORE DIAGNOSTIC TROUBLE CODE P0121 IN THE POWERTRAIN CONTROL MODULE (PCM).

CAUSE:

CURRENT DTC P0121 DIAGNOSTIC CALIBRATION IS TOO SENSITIVE TO HIGH ENGINE LOADS AT IDLE. THE HIGH ENGINE LOADS CAN BE DUE TO POWER STEERING CRAMP, HIGH A/C HEAD PRESSURE, AND HIGH ELECTRICAL DEMANDS.

CORRECTION:

CHECK CALIBRATION SCAN IDENTIFICATION (ID) NUMBER UTILIZING A SCAN TOOL DEVICE. RE-FLASH WITH UPDATED CALIBRATION IF SCAN ID NUMBER IS NOT AS RECENT AS THE CALIBRATIONS LISTED IN THE PARTS SECTION OF THIS BULLETIN. IF THE VEHICLE ALREADY HAS THE MOST RECENT CALIBRATION, THEN REFER TO THE APPROPRIATE SERVICE REPAIR MANUAL TO DIAGNOSE AND REPAIR FOR DTC P0121. TEST DRIVE THE VEHICLE AFTER REPAIR TO ENSURE THAT THE CONDITION HAS BEEN CORRECTED. THE NEW CALIBRATIONS ARE AVAILABLE BEGINNING WITH 1996 CD DISC 17 FROM GM SERVICE TECHNOLOGY GROUP.

**IMPORTANT** THERE ARE THREE METHODS FOR PROGRAMMING A PCM: 1. DIRECT PROGRAMMING. THE VEHICLE IS DIRECTLY CONNECTED VIA THE DATA LINK CONNECTOR (DLC) TO THE DEALER'S/RETAILER'S TECHLINE EQUIPMENT. (T-20 PLUS, T-50 AND T-60 ONLY.) VEHICLE MUST BE PRESENT.

2. REMOTE PROGRAMMING. THE NEW PROGRAM IS DOWNLOADED INTO THE DEALER'S/RETAILER'S SCAN TOOL AND THEN DOWNLOADED INTO THE VEHICLE FROM THE SCAN TOOL VIA THE DLC. TECH 2 REQUIRED. VEHICLE MUST BE PRESENT.

3. OFF-CAR PROGRAMMING. A PCM MAY BE PROGRAMMED WHILE REMOVED FROM THE VEHICLE BY USING THE OFF-BOARD PROGRAMMING ADAPTER (OBPA), P/N J-41207-B. THIS ADAPTER CAN BE CONNECTED TO EITHER THE TECHLINE TERMINAL FOR DIRECT PROGRAMMING OR TO THE SCAN TOOL FOR REMOTE PROGRAMMING. NOT NECESSARY FOR THE VEHICLE TO BE PRESENT.

REFER TO THE APPROPRIATE SERVICE MANUAL OR TECHLINE INFORMATION FOR MORE DETAILED INSTRUCTIONS.

**IMPORTANT** DO NOT ATTEMPT TO ORDER THE CALIBRATIONS FROM GMSPO. THE CALIBRATIONS ARE PROGRAMMED INTO THE VEHICLE'S PCM VIA A TECHLINE TOOL DEVICE.

PARTS INFORMATION

CARLINE CALIBRATION P/N SCAN ID

BUICK RIVIERA:

FED EMISSION 16253214 3214 CALIF EMISSION 16253224 3224 UNLEADED EXPORT EMISSION 16253234 3234

BUICK LESABRE EARLY INTRODUCTION (-WA2): 2.84 AXLE CALIF + FED EMISSION 16252924 2924 2.84 AXLE UNLEADED EXPORT EMISSION 16252934 3934 3.06 AXLE CALIF + FED EMISSION 16252944 2944 3.06 AXLE UNLEADED EXPORT EMISSION 16252954 2954

BUICK LESABRE LATE INTRODUCTION (+WA2): 2.84 AXLE FED EMISSION P205/P215 TIRE 16253024 3024 2.84 AXLE CALIF EMISSION P205/P215 TIRE 16253034 3034 2.84 AXLE EXPORT EMISSION P205/P215 TIRE 16253044 3044 3.06 AXLE FED EMISSION 16253084 3084 3.06 AXLE CALIF EMISSION 16253094 3094 3.06 AXLE UNLEADED EXPORT EMISSION 16253104 3104

OLDSMOBILE 88/REGENCY: 2.84 AXLE FED EMISSION P205/P215 TIRE 16253024 3024 2.84 AXLE CALIF EMISSION P205/P215 TIRE 16253034 3034 2.84 AXLE EXPORT EMISSION P205/P215 TIRE 16253044 3044

OLDSMOBILE LSS:

2.84 AXLE FED EMISSION P225 (QPX) TIRE 16253054 3054 2.84 AXLE CALIF EMISSION P225 (QPX) TIRE 16253064 3064 2.84 AXLE EXPORT EMISSION P225 (QPX) TIRE 16253074 3074 3.06 AXLE FED EMISSION 16253084 3084 3.06 AXLE CALIF EMISSION 16253094 3094 3.06 AXLE UNLEADED EXPORT EMISSION 16253104 3104

PONTIAC BONNEVILLE:

2.84 AXLE FED EMISSION P205/P215 TIRE 16253024 3024 2.84 AXLE CALIF EMISSION P205/P215 TIRE 16253034 3034 2.84 AXLE EXPORT EMISSION P205/P215 TIRE 16253044 3044 3.06 AXLE FED EMISSION 16253084 3084 3.06 AXLE CALIF EMISSION 16253094 3094 3.06 AXLE UNLEADED EXPORT EMISSION 16253104 3104

PONTIAC GRAND PRIX: FED EMISSION 16251794 1794 CALIF EMISSION 16251804 1804 UNLEADED EXPORT EMISSION 16251814 1814

WARRANTY INFORMATION LABOR OPERATION DESCRIPTION TIME J6355 ON-CAR PROM REPROGRAMMING USE PUBLISHED LABOR FLASH E PROM OPERATION TIME

J6352 OFF-CAR PROM REPROGRAMMING USE PUBLISHED LABOR FLASH E PROM OPERATION TIME

FIGURES: 0 ATTACHMENTS: 0

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.