REAR BRAKES DRAG/HEAT UP (ADJUST BRAKE LAMP SWITCH. Pontiac Grand Am 1997

SUBJECT: REAR BRAKES DRAG/HEAT UP (ADJUST BRAKE LAMP SWITCH AND/OR REPLACE PARK BRAKE CABLES)

MODELS: 1995-97 CHEVROLET CAVALIER 1995-97 PONTIAC SUNFIRE 1996-97 PONTIAC GRAND AM

BUILT PRIOR TO VIN BREAKPOINTS:

LOCATION MODEL VIN ======== ===== ===

LANSING (C-SYS) PONTIAC "N" 801616 (M-SYS) PONTIAC "N" 545239 (M-SYS) CHEV. "J" 140121

GENASYS PONTIAC "J" 204577 CHEV. "J" 105599

LORDSTOWN PONTIAC "J" 248525 CHEV. "J" 569130

RAMOS PONTIAC/CHEV. "J" 854112

CONDITION:

SOME OWNERS MAY COMMENT THAT THE REAR BRAKES MAY DRAG/HEAT UP OR REAR OF CAR IS SQUATTING DUE TO AGGRESSIVE REAR BRAKE.

CAUSE:

REAR BRAKE DRAG MAY BE CAUSED BY INCOMPLETE RELEASE OF THE PARKING BRAKE CABLE SYSTEM.

CORRECTION:

DIAGNOSIS OF THE CONDITION SHOULD BE CARRIED OUT AS FOLLOWS:

1. CHECK AND/OR ADJUST BRAKE LAMP SWITCH BY:

REMOVE -

A. DRIVER SIDE SOUND INSULATOR.

B. ELECTRICAL CONNECTION FROM BRAKE SWITCH.

C. ADJUST BRAKE SWITCH AS FOLLOWS:

1995 - PULL BRAKE PEDAL UPWARD WITH APPROXIMATELY 40 POUNDS OF FORCE. SWITCH MAY MOVE IN RETAINER PROVIDING PROPER ADJUSTMENT. NO NOISE INDICATES ADJUSTMENT WAS CORRECT.

1996-97 - SOME LATE 1996 AND 1997 J-MODELS MAY HAVE A NEW STYLE BRAKE SWITCH. TO ADJUST THIS NEW STYLE SWITCH, ROTATE STOP LAMP SWITCH COUNTER-CLOCKWISE APPROXIMATELY 45 DEGREES IN RETAINER UNTIL SWITCH STOPS. PULL SWITCH TOWARD REAR OF VEHICLE AND THEN PUSH TOWARDS FRONT OF VEHICLE UNTIL SWITCH BOTTOMS OUT AGAINST BRAKE PEDAL (SEE "IMPORTANT" STATEMENT BELOW) AND SWITCH ACTUATOR IS FULLY DEPRESSED. SNAP BRAKE SWITCH INTO RETAINER BY TURNING CLOCKWISE 45 DEGREES UNTIL A CLICK IS HEARD.

IMPORTANT:

BRAKE PEDAL MUST BE IN REST POSITION DURING ABOVE ADJUSTMENT PROCEDURE.

INSTALL -

A. ELECTRICAL CONNECTION TO BRAKE SWITCH.

B. DRIVER SIDE SOUND INSULATOR.

REQUIRED ADJUSTMENT - AFTER ADJUSTMENT, PROCEED TO STEP 3 (CHECKING FRONT AND REAR BRAKES) AND THEN STEP 2.

BRAKE SWITCH FOUND PROPERLY - PROCEED TO STEP 2.

2. ELEVATE REAR WHEELS AND CHECK FOR LOW TURNING EFFORT BY HAND:

FREE - CYCLE PARK BRAKE 3-4 TIMES AND RE-EVALUATE DRAG. IF DRAG CANNOT BE DUPLICATED UNDER CUSTOMER CONDITIONS OF USAGE, ENVIRONMENT, ETC., RETURN TO SERVICE.

NOT FREE - PROCEED TO STEP 3.

3. ON WHEELS THAT ARE DRAGGING, REMOVE WHEEL AND BRAKE DRUM FOR DIAGNOSIS. INSPECT THE DRUM/LININGS FOR SIGNS OF OVERHEATING (CRACKED OR CRUMBLING BRAKE LINING, BLUE COLORATION OF BRAKE DRUM OR BRAKE SHOE WEB, UNUSUAL ODOR, ETC. DAMAGED LININGS AND DRUM(S) SHOULD BE REPLACED AND THE OTHER BRAKE COMPONENTS SHOULD BE INSPECTED AND SERVICED FOR DAMAGE (I.E., WHEEL BEARING ASSEMBLY, PARKING BRAKE CABLE, WHEEL CYLINDER, ETC.).

OVERHEATED - AFTER MECHANICAL REPAIR, RETURN TO STEP 2.

NOT OVERHEATED - PROCEED TO STEP 4.

4. WITH PARK BRAKE LEVER RELEASED, PULL BACK THE FRONT CABLE AT THE REAR AXLE CONNECTION. THIS WILL CREATE "SLACK" IN THE SYSTEM THAT HAD BEEN TAKEN UP BY THE SELF-ADJUST MECHANISM. THIS PLACES THE CABLE IN THE FULLY RELEASED POSITION. RECHECK WHEEL TURNING EFFORT TO INSURE WHEEL TURNS EASILY BY HAND.

FREE - PROCEED TO STEP 6 TO EVALUATE FRONT PORTION OF THE PARK BRAKE SYSTEM.

NOT FREE - CONCERN MAY BE IN REAR BRAKE ASSEMBLY OR REAR PARK BRAKE CABLE(S). PROCEED TO STEP 5.

5. REVIEW MECHANICAL OPERATION OF REAR BRAKES AND CABLES TO LOOK FOR DISCREPANT OR MIS-ASSEMBLED PART(S). INSPECT REAR BRAKE CABLE FOR PHYSICAL CONDITION, CORRECT ROUTING INTO AND INSIDE THE REAR BRAKE ASSEMBLIES AND FOR FREEDOM OF INTERFERENCE WITH ADJACENT PARTS. WITH DRUMS INSTALLED, CHECK FOR PROPER ACTUATION OF THE SHOES BOTH HYDRAULICALLY AND WITH THE PARK BRAKE LEVER.

THE CURRENT REAR PARK BRAKE CABLE IS P/N 22651234 AND IS IDENTIFIED BY RED TAPE. IF REPLACEMENT IS NECESSARY, VERIFY THAT THE CABLE BEING INSTALLED IS THE CORRECT PART NUMBER.

CHECK THE OPERATION OF THE PARK BRAKE SYSTEM BY FULLY APPLYING IT 3-4 TIMES (TO FULLY ADJUST) AND RECHECK WHEEL TURNING EFFORT TO INSURE WHEEL TURNS EASILY BY HAND.

FREE - PROCEED TO STEP 6 TO RE-EVALUATE THE FRONT PORTION OF THE PARK BRAKE SYSTEM.

NOT FREE - REVIEW MECHANICAL OPERATION OF BRAKE AND/OR CABLE TO LOOK FOR DISCREPANT OR MIS-ASSEMBLED PARTS.

6. INSPECT FRONT PARK BRAKE CABLE AND LEVER ASSEMBLY FOR PROPER INSTALLATION AND OPERATION. CABLE SHOULD BE INSPECTED FOR PINCHES (ESPECIALLY NEAR DRIVER'S INBOARD SEAT TRACK AND REAR CONSOLE BRACKET), KINKS, NICKS, OR CUTS IN CABLE STRAND COATING, ETC.

THE PARKING BRAKE CABLE WIRE STRAND IS COATED WITH A PLASTIC MATERIAL THAT SLIDES AGAINST NYLON SEALS INSIDE THE CONDUIT END FITTINGS. THIS PLASTIC COATING IS FOR CORROSION PROTECTION AND REDUCED PARKING BRAKE EFFORT. HANDLING OF THESE CABLES DURING SERVICING OF THE PARKING BRAKE SYSTEM REQUIRES A LITTLE EXTRA CARE. DAMAGE TO THE PLASTIC COATING WILL REDUCE CORROSION PROTECTION AND IF THE DAMAGED AREA PASSES THROUGH THE SEAL, IT MAY DAMAGE THE SEAL AND CAUSE THE CABLE TO SNAG AND NOT FULLY RELEASE. CONTACTING THE COATING WITH SHARP-EDGED TOOLS OR WITH SHARP SURFACES OF THE VEHICLE UNDERBODY SHOULD BE AVOIDED.

IMPORTANT:

PLASTIC COATED PARKING BRAKE CABLES DO NOT NEED PERIODIC LUBRICATION.

TO CHECK OPERATION OF THE CABLE, DISCONNECT BOTH THE ENDS OF THE FRONT PARKING BRAKE CABLE TO VERIFY THE CABLE STRAND MOVES FREELY BY HAND FROM EITHER END (APPROXIMATELY 5-10 LB. FORCE):

DAMAGE/INSUFFICIENT OPERATION - REPLACE FRONT CABLE, P/N 22603399.

AFTER REPLACEMENT, RETURN TO STEP 2 FOR VERIFICATION.

7. THE PARK BRAKE LEVER SHOULD BE INSPECTED FOR PROPER OPERATION AND FOR THE SELF-ADJUST FEATURE. IT MAY BE CHECKED BY PULLING THE CABLES DOWN AT THE REAR AXLE AS IN STEP 4 AND CYCLING THE SYSTEM 3-4 TIMES. WHILE CYCLING THE SYSTEM, HOLD THE RELEASE BUTTON IN AS THIS WILL ALLOW YOU TO HEAR THE ADJUSTMENT "CLICKS". AFTER RE-INSTALLING THE CONSOLE ASSEMBLY, RECHECK FOR BRAKE DRAG AND POSSIBLY A FEELING OF "TIGHTNESS" AT THE LEVER ASSEMBLY.

DRAGGING AND/OR "TIGHTNESS" OF OPERATION - RECHECK FRONT AND/OR REAR PARK BRAKE CABLES FOR POSSIBLE MIS-ROUTING OR CABLE DAMAGE. REPAIR AND RE-EVALUATE WITH STEP 2.

FREE/NORMAL - VERIFY NO DRAG CONDITION EXISTS AND RETURN VEHICLE TO SERVICE.

PARTS INFORMATION:

DESCRIPTION OLD P/N NEW P/N =========== ======= =======

PARKING BRAKE CABLE ASSEMBLY - 22636670 22603399 FRONT

PARTS ARE CURRENTLY AVAILABLE FROM GMSPO.

WARRANTY INFORMATION:

FOR VEHICLES REPAIRED UNDER WARRANTY, USE:

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

N2700 SWITCH, STOP LAMP - USE PUBLISHED LABOR ADJUST OPERATION TIME

H2880 CABLE, PARKING BRAKE - USE PUBLISHED LABOR REPLACE RIGHT REAR OPERATION TIME

H2881 CABLE, PARKING BRAKE - USE PUBLISHED LABOR REPLACE LEFT REAR OPERATION TIME

H2887 CABLE, PARKING BRAKE - USE PUBLISHED LABOR REPLACE BOTH REAR OPERATION TIME

H2882 CABLE, PARKING BRAKE - USE PUBLISHED LABOR REPLACE FRONT OPERATION TIME

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.