CAMPAIGN: OMISSION OF LOW OIL PRESSURE WARNING ON THE ENG.
SUBJECT: OMISSION OF LOW OIL PRESSURE WARNING ON THE ENGINE ALARM/SHUTDOWN FEATURE
MODELS: 1995 C6, C7 MEDIUM DUTY TRUCKS, B7 SCHOOL BUSES AND P6 MODELS EQUIPPED WITH DIESEL ENGINES (RPO LXO) AND ENGINE ALARM SHUTDOWN FEATURE (RPO KPJ)
General Motors has determined that on CERTAIN 1995 C6 and C7 Medium Duty Trucks, B7 School Buses and P6 Models equipped with diesel engines (RPO LXO) and the automatic engine shutdown option (KPJ) and built before March 24, 1995, the "Low Oil Pressure" feature was not provided in the released design. Without this feature (which the customer paid for) if a "low oil pressure" condition occurred, the driver would not receive the expected warning and severe engine damage could occur.
To correct this condition, dealers will replace the existing circuit board in the shutdown module with one containing a jumper to pin A7.
VEHICLES INVOLVED
Involved are CERTAIN 1995 C6 and C7 Medium Duty trucks, B7 School Buses and P6 Models equipped with diesel engines (RPO LXO) and engine alarm and shutdown feature (RPO KPJ) built within the following VIN breakpoints:
Year Model From Through
1995 GMC SJ500014 SJ519883 1995 Chevrolet SJ100106 SJ111188
The specific vehicles involved in this campaign have been identified by Vehicle Identification Number (VIN) Computer Listings. These listings are furnished to all involved dealers with the campaign bulletin. Dealers should confirm vehicle eligibility through VISS (Vehicle Information Service System) or SERVICENET prior to beginning campaign repairs.
DEALER CAMPAIGN RESPONSIBILITY
All unsold vehicles in dealers' possession and subject to this campaign MUST be held and inspected/repaired per the service procedure of this campaign bulletin BEFORE owners take possession of these vehicles.
Dealers are to service all vehicles subject to this campaign at no charge to owners, regardless of mileage, age of vehicle, or ownership, from this time forward.
Owners of vehicles recently sold from your vehicle inventory are to be contacted by the dealer and arrangements made to make the required correction according to instructions contained in this bulletin.
In summary, whenever a vehicle subject to this campaign enters your vehicle inventory, or is in your dealership for service in the future, please take the steps necessary to be sure the campaign correction has been made before selling or releasing the vehicle.
If the name and address of the owner of an involved vehicle was unavailable to GMC Truck Division at the time of campaign initiation, the dealer must determine the owner's name and address from the dealership sales records. Please provide this information directly on the second copy of the listing next to the applicable VIN so that our records may be updated and the appropriate notification mailed to the owner. This second copy should then be submitted to the address listed below in the previously supplied yellow campaign envelopes.
GMC Truck Division General Motors Corporation 101 Union Street Plymouth, Michigan 48170 OWNER NOTIFICATION ------------------ Owners will be notified of this campaign on their vehicles by GMC Truck Division (see copy of owner letter included with this bulletin). A listing of owner names and addresses has been furnished to the involved dealers to enable dealers to follow up with owners involved in this campaign. This listing may contain owner names and addresses obtained from State Motor Vehicle Registration records. The use of such motor vehicle registration data for any other purpose is a violation of law in several states. Accordingly, you are urged to limit the use of this listing to this campaign.
SERVICE PROCEDURE
NOTICE: Many solid state electrical components can be damaged by Electrostatic Discharge (ESD). Some will display a symbol but many will not. Be sure to follow the ESD Sensitive procedures listed in the 1995 TopKick/Kodiak, P6 Forward Chassis Service Manual, Section 8C "Handling Electrostatic Discharge Sensitive Parts" when performing the following procedure. Failure to do so could result in damage to the instrument cluster components.
1. Disconnect the negative battery cable.
2. TopKick/Kodiak Models - Remove the left floor vent duct.
3. Locate the engine alarm/shutdown module. The module is in a black plastic case.
TopKick/Kodiak Models - The module is located on the LH side of the vehicle, above the kick panel on the vertical sheet metal, near the floor vent duct and behind the Instrument Panel (I/P).
B7 School Bus Models - Module location is behind the center of the Instrument Panel (I/P), attached to a center support.
P6 Models - The module is located on the LH side of the steering column behind the instrument panel (I/P) and attaches to the I/P cluster bracket.
4. Disconnect the wiring harness from the circuit board. Squeeze the blue main wiring harness connector to remove.
5. Disconnect the four prong pigtail from the main harness connector.
6. Unsnap the module case cover. The cover has four snaps, two on each side. It is not necessary to remove the cover from the module assembly.
TopKick/Kodiak Models - Unsnap only the inboard side of the case. The case has a left hand hinge and opens right to left. This is a blind operation.
B7 School Bus Models - Remove the RH I/P access panel for module access. Remove only the closest module fastening screw and rotate the module case counterclockwise for circuit board access.
P6 Models - Unsnap only the inboard side of the case.
7. Remove the circuit board from the module case and discard the board.
TopKick/Kodiak Models - Gently wiggle the circuit board to remove it from the case, discard the board. This is a blind operation.
B7 School Bus Models - Remove the circuit board from the case and discard the board.
P6 Models - Remove the circuit board from the case and discard the board.
8. Install a new circuit board into the module case. Position the four prong pigtail in the module case access slot and close the cover.
IMPORTANT: If the module case cover was removed for any reason, the cover MUST be installed with the hole for the speaker located toward the top of the module.
9. Reconnect the four prong pigtail into the main harness connector.
10. Reconnect the blue main wiring harness connector into the circuit board.
11. TopKick/Kodiak Models - Reinstall the left floor vent duct.
12. Reconnect the negative battery cable.
13. Install "Campaign Identification Label".
PARTS INFORMATION
Parts are to be obtained from General Motors Service Parts operation (GMSPO). To ensure parts are obtained as soon as possible, order them from GMSPO on a C.I.O. order with no special instruction code but order under an advise code (2). All Goodwrench parts system test dealers should order on a "VIP" order.
Part Number Description Part Restrictions Vehicle Quantity Models -------------------------------------------------------------------------- 15727949 Engine Alarm and LXO & KPJ & JE4 C6,C7 1 Shutdown Module 15727950 Engine Alarm and LXO & KPJ & JE3 C6,C7 1 Shutdown Module 15727951 Engine Alarm and LXO & KPJ & JE3 B7,P6 1 Shutdown Module 15727952 Engine Alarm and LXO & KPJ & JE4 B7,P6 1 Shutdown Module
WARRANTY INFORMATION
Dealers should submit a warranty claim on each vehicle completed under this campaign.
Labor Operation *Time Cause Number Description Allowance Code ----------------------------------------------------------------------- V9715 R & R Engine Alarm/Shutdown Module 0.4 96
*For dealer to receive Administrative Time Allowance associated with this campaign, add 0.1 hour to the Labor Operation Time Allowance.
CAMPAIGN IDENTIFICATION LABEL
Each vehicle corrected in accordance with the instructions outlined in this product campaign bulletin will require a "Campaign Identification Label." Each label provides a space to include the campaign number and five (5) digit dealer code of the dealer performing the campaign service. This information must be inserted with a typewriter or ball point pen. This label is to be used in conjunction with the clear protective plastic cover provided with the Campaign Identification Labels.
Each "Campaign Identification Label" is to be located on the radiator core support in an area which will be visible when the vehicle is brought in for periodic servicing by the owner.
Apply "Campaign Identification Label" only on a clean, dry surface.
Additional Campaign Identification Labels and covers are available in sheets of 49 by calling VISPAC, Incorporated at 1-800-269-5100 (Monday through Friday 8:00 AM to 4:30 PM EST).
ADMINISTRATIVE PROCEDURE
Procedures covering this campaign are outlined in Section V of your dealership's "GMC Truck Warranty Claims Processing Manual" #P9119 Rev. 2/94.
Dear GMC Truck Customer:
As a valued customer, your complete satisfaction with your GMC truck is our goal. In keeping with this goal, we want to let you know that we have discovered a problem that could affect your vehicle and we want to take care of it at no charge to you.
On a number of 1995 C6 and C7 Medium Duty Trucks, B7 School Buses and P6 Models equipped with diesel engines (RPO LXO) and the automatic engine shutdown option (KPJ) and built before March 24, 1995, the "Low Oil Pressure" feature was not provided in the released design. Without this feature, if a "low oil pressure" condition occurred, the driver would not receive the expected warning and severe engine damage could occur.
To be absolutely sure that your vehicle is to specifications, we will replace the existing circuit board in the shutdown module with a new circuit board.
Instructions for performing this service have been sent to your GMC Truck dealer, and parts are available. Please contact your GMC dealer to arrange a service date as soon as possible. This procedure will take about 25 minutes to complete, but you should ask how much additional time your dealer will need to schedule and process your vehicle.
The enclosed postage paid owner reply card identifies your vehicle. Presentation of this card to your dealer will assist in making the necessary correction to your vehicle in the shortest possible time. If you have sold or traded your vehicle, please furnish us the complete name and address of the person you sold or traded your vehicle to and return the card to us.
We are sorry to cause you this inconvenience; however, we have taken this action in the interest of your continued satisfaction with our product.
GMC TRUCK DIVISION General Motors Corporation
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.
