INFO. 'ELECTRICAL CENTER' DIAGNOSTIC INFORMATION. Chevrolet S10 Pickup

SUBJECT: INFORMATION - "ELECTRICAL CENTER" DIAGNOSTIC INFORMATION

MODELS: 1997-98 BUICK CENTURY, PARK AVENUE, REGAL 1998 CADILLAC SEVILLE 1997-98 CHEVROLET CORVETTE, MALIBU, VENTURE 1997-98 OLDSMOBILE CUTLASS, SILHOUETTE 1998 OLDSMOBILE INTRIGUE 1997-98 PONTIAC GRAND PRIX, TRANS SPORT

1998 CHEVROLET AND GMC S/T MODELS

THE ABOVE LISTED VEHICLES USE AN UNDERHOOD AND/OR BODY LOCATED FUSE/RELAY CENTER, ALSO CALLED A JUNCTION BLOCK OR BUSSED ELECTRICAL CENTER (BEC) WHICH PROVIDES A COMMON LOCATION FOR FUSES, CIRCUIT BREAKERS, AND RELAYS. BUSSED ELECTRICAL CENTERS CONTAIN INSULATED LAYERS OF METAL BUSSING AND TERMINALS PERMANENTLY SANDWICHED BETWEEN AN UPPER AND LOWER HOUSING. THE CENTER PROVIDES A POWER AND SIGNAL DISTRIBUTION LOCATION TO WHICH THE VEHICLE'S HARNESSES PLUG.

THE HOUSING AND THE FEMALE TERMINALS WHERE DEVICES PLUG INTO MAY BE DAMAGED BY IMPROPERLY PROBING TERMINALS. THE USE OF A STANDARD DIGITAL MULTIMETER LEAD OR THE PROBE FROM A TEST LIGHT WILL CAUSE DAMAGE IN THIS AREA. IF INTERFACE DAMAGE OCCURS, THE CENTER'S FEMALE TERMINALS ARE NOT SERVICEABLE. THE ELECTRICAL CENTER ASSEMBLY MUST BE REPLACED. HARNESS CONNECTOR TERMINALS REMAIN SERVICEABLE AND CAN BE REPLACED IF NECESSARY.

ANYTIME ANY FEMALE TERMINAL IS PROBED, THERE IS A RISK OF CAUSING AN OPEN OR INTERMITTENT CIRCUIT AT THE TERMINAL INTERFACE FROM MECHANICAL DAMAGE. TO MINIMIZE THE RISK OF DAMAGE, PLEASE OBSERVE THE FOLLOWING PROCEDURES WHEN PERFORMING DIAGNOSIS:

1. IF THE DEVICE SIDE OF THE ELECTRICAL CENTER IS BEING PROBED, THEN THE CONNECTOR TEST ADAPTER KIT (J35616-A) OR THE MATING TERMINAL FROM THE REPLACEMENT TERMINAL KIT (J38125-A) MUST BE USED. CAREFULLY FOLLOW THE INSTRUCTIONS SPECIFIED IN THE J35616-A CONNECTOR TEST KIT AND USE THE DIAGNOSTIC PROBE TOOL HAVING SAME BLADE DIMENSIONS AS THE DEVICE AND FOLLOW THESE COMMON RULES.

O THE PROBE TIP SHOULD BE INSERTED STRAIGHT INTO THE CAVITY AND KEPT STABLE DURING TESTING.

O DO NOT WIGGLE OR MOVE THE PROBE TIP ONCE IT HAS BEEN INSERTED INTO THE TERMINAL.

O THE NUMBER OF PROBE INSERTIONS SHOULD BE KEPT TO ONE.

2. DO NOT DISASSEMBLE THE BODY OF THE ELECTRICAL CENTER TO REPAIR AND/OR REPLACE FEMALE TERMINALS. IF NECESSARY, AFTER PROPER DIAGNOSIS HAS BEEN PERFORMED, REPLACE THE ENTIRE ELECTRICAL CENTER ASSEMBLY.

THE ONLY REPAIRS THAT MAY BE MADE TO THE ELECTRICAL CENTER ARE REPLACEMENT OF PLUG-IN DEVICES AND MOUNTING HARDWARE, AS FOLLOWS:

O FUSES, RELAYS, AND CIRCUIT BREAKERS O ELECTRICAL CENTER COVER, BATTERY STUD COVER, AND OTHER SNAP-ON COVERS O COVER ATTACHMENT THUMB SCREW O LABELS FOR FUSE/RELAY IDENTIFICATION O SPLASH SHIELDS O MOUNTING BRACKETS

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.