CAMPAIGN: LOW ENGINE OIL PRESS WARNING SYS./PROM AVAIL.

MODELS AFFECTED: 1987 RIVIERA

CONDITION

General Motors has determined that certain 1987 Buick Rivieras were produced with a low engine oil pressure warning system that could malfunction resulting in an erroneous low engine oil pressure warning to the vehicle driver.

To prevent the possibility of this condition occurring, installation of a new EPROM in the body computer module (BCM) is required.

VEHICLES INVOLVED

Involved are certain 1987 Buick Riviera models within the following VIN breakpoints:

Model Year Plant Beginning Up To And Including ---- ----- --------- -------------------- 1987 Hamtramck Start of Production HU406896

DEALER ACTION

Dealers are to service all vehicles subject to this campaign at no charge to the owner, regardless of mileage, age of vehicle, or ownership, from this time forward.

Whenever a vehicle subject to this campaign is taken into your new or used vehicle inventory, or it is in your dealership for service in the future, you should take the steps necessary to be sure the campaign correction has been made before reselling or releasing the vehicle.

Owners of vehicles recently sold from your new vehicle inventory are to be contacted by the dealer and arrangements made to make the required modification according to the instructions contained in this bulletin.

PARTS INFORMATION

Parts required to complete this correction are to be obtained from General Motors Service Parts Operations (GMSPO). To ensure these parts will be obtained as soon as possible, they should be ordered from GMSPO on a C.I.O. order with NO special instruction code, but on an advise code (2).

Description Part Number Quantity ----------- ----------- -------- EPROM 16075601 1

TECHNICAL PROCEDURE

1. Open instrument panel compartment door.

2. Remove 10 screws attaching instrument panel compartment box to instrument panel.

3. Remove instrument panel compartment by sliding rearward.

NOTE: Instrument panel compartment door remote latch actuator cable retainer clip may hang up at top right. If this occurs, it will be necessary to carefully apply a downward pressure on top of the clip in order to remove the instrument panel compartment. This can be accomplished by using a flat blade type tool such as J-24595-B (door pad trim pad and arnish clip remover).

4. With ignition switch off, remove electrical connectors from BCM and remove attaching bracket to BCM.

5. Remove BCM.

6. Remove four screws from access cover and remove cover. Refer to Figure 1.

7. Remove EPROM as follows: Using the rocker type PROM removal tool(Figure 1), engage one end of the EPROM carrier with the hook end of the tool. Press on the vertical bar end of the tool and rock the engaged end of the EPROM carrier up as far as possible. Engage the opposite end of the EPROM carrier in the same manner and rock this end up as far as possible. Repeat this process until the EPROM carrier and the EPROM are free of the EPROM socket.

8. Install EPROM, mounted in carrier, in EPROM socket. Small notch in carrier must be aligned with small notch in socket. Press on EPROM carrier until it is firmly seated in the socket. Do not press on EPROM, only the carrier.

9. Install access cover and secure with four screws.

10. Reinstall BCM (reverse Steps 1 through 4).

NOTE: If difficulty was encountered removing instrument panel compartment, due to actuator cable retainer clip; installation will be made easier by removing screw that holds clip, turning clip over, and reinstalling screw.

11. Clear BCM malfunction code

To clear BCM codes, enter diagnostics by simultaneously touching the CRT Climate Control pages "OFF" and "WARM" pads until you hear a double beep. The steps indicated in the following flow chart outline how to clear BCM codes using the Graphic Control Center (GCC).

12. Install A Campaign Identification Label

Each vehicle modified in accordance with the instructions outlined in this procedure will require a Campaign Identification label. Each label provides a space to include the campaign number, the five provides a space to include the campaign number, the five (5) digit dealer code of the dealer performing the campaign service, and the date vehicle was campaigned. This information may be inserted with a typewriter or ballpoint pen. When installing label, clean the surface of the radiator upper mounting support and apply the campaign label where it is readily visible.

WARRANTY INFORMATION

SUBLET PART FAILED PARTS FAILURE LABOR LABOR OTHER DEALER OPER. COUNT PART NO. ALLOW. CODE OP NO HOURS HOURS MTL TWG ----- ----- -------- ------ ------ ----- ----- ----- ------- Replace EPROM 1 16075601 $31.55 96 V3941 . 6 *.1 ---

* .1 hour clerical administration may be added to the above operation.

Dear Buick Owner:

General Motors has determined that some 1987 Buick Riviera models were produced with a low engine oil pressure warning system that could malfunction, resulting in an erroneous low engine oil pressure warning to the vehicle driver.

To correct this condition on your vehicle, your Buick dealer will install a new EPROM (integrated circuit board) in the body computer module. This service will be performed for you at no charge.

It is important that this service is done so that your vehicle's low engine oil pressure warning system will only indicate conditions which might result in extensive engine damage.

Instructions for performing this repair have been sent to your Buick dealer. Please contact your Buick dealer to arrange a service date. The labor time to perform this repair is approximately 40 minutes. Please ask your dealer if you wish to know how much additional time will be required to process your vehicle.

The enclosed owner reply card , identifies your vehicle. Presentation of this card to your dealer will assist in making the necessary correction in the shortest possible time. If you have sold or traded your vehicle, please let us know by completing the postage paid owner reply card and returning it to us so that we may update our records. Should your dealer not schedule a service date within a reasonable time, you should contact the Buick Customer Assistance Department, Flint Home Office by calling 800-521-7300.

We are sorry to cause you this inconvenience; however, we have taken this action in the interest of your continued satisfaction with our products.

BUICK MOTOR DIVISION

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.