GM Service Manual Online
For 1990-2009 cars only

HEADLAMPS AND PARK LAMPS INTERMITTENTLY TURN OFF

SUBJECT: HEADLAMPS AND PARK LAMPS INTERMITTENTLY TURN "OFF" WHEN TURNING HIGH BEAMS "ON" (SPLICE A NEW CIRCUIT)

MODELS: 1997 BUICK LESABRE - BUILT WITH VIN BREAKPOINTS 463324 THROUGH 480000 AND RPO +WA2

CONDITION:

SOME OWNERS MAY COMMENT THAT THE HEADLAMPS (LOW AND HIGH BEAM) AND PARK LAMPS MAY INTERMITTENTLY TURN "OFF" WHEN ATTEMPTING TO TURN "ON" THE HIGH BEAMS AND THE VEHICLE IS UNDER THE FOLLOWING CONDITIONS:

O GEAR SELECTOR: PARK O TWILIGHT SENTINEL DELAY SWITCH: ON O HEADLAMP SWITCH: OFF

CAUSE:

WHEN THE HEADLAMP DIMMER SWITCH IS CYCLED, GROUND SHIFTS IN THE WIRING BETWEEN THE LAMP DIMMER SWITCH AND THE LAMP CONTROL MODULE (LCM) MAY CAUSE THE LCM TO INTERPRET THE TWILIGHT SENTINEL DELAY SWITCH (LOCATED IN THE LAMP DIMMER SWITCH ASSEMBLY) AS BEING IN THE OFF POSITION.

IMPORTANT:

THE LCM NORMALLY TURNS OFF ALL EXTERIOR LAMPS WHENEVER THE TWILIGHT SENTINEL SWITCH IS OFF AND THE GEAR SELECTOR IS IN PARK.

CORRECTION:

REFER TO THE SCHEMATICS ON PAGES 8A-100-6 AND 8A-100-7 IN THE 1997 "H" FINAL SERVICE MANUAL.

IMPORTANT: DO NOT USE THE SCHEMATICS LOCATED IN THE 1997 LESABRE PRELIMINARY SERVICE MANUAL.

1. LOCATE THE WIRE IN HEADLAMP DIMMER SWITCH CONNECTOR CAVITY G (CKT 251, BLK/WHT). CUT THE WIRE APPROXIMATELY 6 INCHES FROM THE CONNECTOR AND TIE BACK THE EXCESS HARNESS WIRE WITH ELECTRICAL TAPE.

2. USING APPROXIMATELY 5 FEET OF WIRE, SPLICE A NEW CIRCUIT (0.5 MM(2)) FROM THE END OF THE REMAINING WIRE IN THE LAMP DIMMER SWITCH CONNECTOR CAVITY G TO THE LAMP CONTROL MODULE (LCM) CONNECTOR CAVITY A4, TERMINAL P/N 12089660.

IMPORTANT:

CAVITY A4 OF THE LCM CONNECTOR IS EMPTY AND CKT 1349 (BRN) IS NOT USED ON THIS VEHICLE, AS INDICATED BY THE SCHEMATIC ON PAGE 8A-100-6 IN THE 1997 "H" FINAL SERVICE MANUAL.

PARTS INFORMATION:

PARTS ARE CURRENTLY AVAILABLE FROM GMSPO.

WARRANTY INFORMATION:

FOR VEHICLES REPAIRED UNDER WARRANTY, USE:

LABOR OPERATION NUMBER DESCRIPTION LABOR TIME =============== ============ ==========

N6363 WIRING AND/OR CONNECTOR - 0.9 HR REPAIR I/P DIMMER/ILLUMINATION SWITCH

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.