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CAMPAIGN: 4.9 LITER ENGINE PCM MEM-CAL/PROM REPLACEMENT

PRODUCT EMISSION CAMPAIGN

SUBJECT: CAMPAIGN 96033 - 4.9 LITRE ENGINE PCM MEM-CAL/PROM REPLACEMENT --------------------------------------------------------------

MODELS: CERTAIN 1991-1995 CADILLAC VEHICLES EQUIPPED WITH 4.9 LITRE ENGINE ------------------------------------------------------------------ (RPO L26) ---------

DEFECT INVOLVED

General Motors of Canada Limited has determined that 1991-1995 model Cadillacs equipped with 4.9 litre engines may require modifications in order to help reduce emissions of carbon monoxide and hydrocarbons.

In October 1991, General Motors implemented a change in its production of 1992 model Cadillacs equipped with 4.9 litre engines that introduced an enrichment calibration to the fueling strategy. This calibration was subsequently included in production of 1993-1995 model Cadillacs equipped with 4.9 litre engines and in service parts received by certain 1991-1992 model Cadillacs equipped with 4.9 litre engines. It has been alleged that this calibration has a detrimental effect on a vehicle's emission control system and that this calibration was not adequately reported to the U.S. Government.

General Motors of Canada Limited will modify the fueling strategy for these vehicles in a way that reduces the emission of air pollutants from the vehicles without compromising driveability. All vehicles that were built with the fueling strategy in question or which subsequently received the strategy through a service PROM are being recalled to have the calibration inspected and, if necessary, revised via the installation of a new service PROM.

VEHICLES INVOLVED

Certain 1991-1995 model Cadillac vehicles equipped with 4.9 litre engines (RPO L26) require inspection and/or replacement of the PCM Mem-Cal/PROM as indicated below. Note that vehicles equipped with 4.9 litre engines can be easily identified by the character "B" in the 8th position of the Vehicle Identification Number.

Inspect To Determine If PCM Mem-Cal/PROM Replacement Is Necessary ----------------------------------------------------------------- Certain 1991 model C, E, and K vehicles that received a service PROM through a previous warranty repair.

Certain 1992 model vehicles that received a service PROM through a previous warranty repair and built prior to the following breakpoints:

C - 247931 E - 604014 K -806500

Replace PCM Mem-Cal/PROM - Inspection Not Necessary --------------------------------------------------- All 1992 model vehicles built after the following breakpoints:

C - 247930 E - 604013 K -806499

All 1993 model vehicles except Allante, Eldorado Touring Coupe, Eldorado Sport Coupe, Seville Touring Sedan and Fleetwood Sedan.

All 1994-1995 model DeVilles. Note that DeVille Concours is not included.

Notice: Since some vehicles did not receive a service PROM through a previous warranty repair or are otherwise excluded from this recall, it is very important that dealers confirm vehicle eligibility through the DCS Screen 445 prior to performing this campaign.

Involved vehicles have been identified by Vehicle Identification Number. Computer listings containing the complete Vehicle Identification Number, customer name and address data have been prepared, and are being furnished to involved dealers with the campaign bulletin. The customer name and address data furnished will enable dealers to follow-up with customers involved in this campaign. Any dealer not receiving a computer listing with the campaign bulletin has no involved vehicles currently assigned.

PARTS INFORMATION

Parts required to complete this campaign are to be obtained from General Motors Service Parts Operations (GMSPO). Please refer to your "involved vehicles listing" and CHECK TABLE 2 of this bulletin for service part information prior to ordering requirements.

Due to the low number of vehicles involved and the limited availability of these parts, dealers should not order the following campaign part numbers for use as shelf stock.

16242431 16242463 16242443 16242483

These campaign part numbers should only be ordered by dealers when an affected vehicle requires repair at their dealership.

CUSTOMER NOTIFICATION

All customers of record at the time of campaign release are shown on the attached computer listing and have been notified by first class mail from General Motors (see copy of customer letter included with this bulletin). The listings provided are for campaign activity only and should not be used for any other purpose.

In order to ensure full protection under the emission warranty, and the right to participate in future recalls, the customer notification letter recommends that customers have their vehicles serviced as soon as possible. It also advises that failure to do so could legally be determined to be lack of proper maintenance, and that the vehicle may fail a provincial or local emission inspection test if the recall work is not completed. Additionally, if the dealer finds that the emission system has been intentionally disabled, the letter explains that the cost of system restoration, so that it will function as designed, is the responsibility of the customer.

Regardless of whether the owner decides to have an intentionally disabled emission system repaired, the dealer should perform the campaign correction unless it is determined that performing the remedy without repairing the intentionally disabled emission system might create a risk of accident or injury.

COURTESY TRANSPORTATION

The availability of courtesy transportation to customers whose vehicles are involved in this campaign is of the utmost importance in maintaining customer satisfaction. Dealers are to take the steps necessary to ensure that these customers clearly understand that courtesy transportation is available and will be provided upon request at no charge. Dealers should submit such claims in the normal manner and appropriate credit will be issued.

DEALER CAMPAIGN RESPONSIBILITY

All unsold new vehicles in dealer's possession and subject to this campaign must be held and inspected/repaired per the service procedure of this campaign bulletin before customers take possession of these vehicles.

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

Customers who have recently purchased vehicles sold from your vehicle inventory, and for which there is no customer information indicated on the dealer listing, are to be contacted by the dealer. Arrangements are to be made to make the required correction according to the instructions contained in this bulletin. This could be done by mailing to such customers a copy of the appropriate customer letter accompanying 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, you must take the steps necessary to be sure the campaign correction has been made before selling or releasing the vehicle.

SERVICE PROCEDURE

The following service procedure is to be performed on certain 1991-1995 model Cadillac vehicles equipped with the 4.9 litre engine (RPO L26), which can be easily identified by the character "B" in the 8th position of the Vehicle Identification Number.

It is important to note that some 1991 and 1992 model vehicles built before October 24, 1991 may have experienced warranty repairs with a labor operation code of T6527 or J6364 and received the PROM being recalled as a service part. VIN breakpoints for 1992 model vehicles are:

247930 for DeVille 604013 for Eldorado 806499 for Seville

Affected 1991 model vehicles and 1992 model vehicles built before these breakpoints should be inspected and repaired if necessary. Dealers must confirm vehicle eligibility through the DCS Screen 445 and/or their "involved vehicles listing" prior to performing this inspection. All 1992 model vehicles built after the breakpoints require Mem-Cal replacement using the following procedure.

1. Determine the PROM ID number by using the appropriate procedure which follows. Note that the use of a Tech 1 diagnostic tool for this purpose is specifically NOT recommended.

- Turn ignition key to the "RUN" position.

- Simultaneously press and hold the "OFF" and "WARMER" buttons on the Electronic Climate Control (ECC) panel until all segments on the ECC and Fuel Data Center (FDC) panel are illuminated. Then release the buttons.

A. All 1991-1993 model C

- Observe the FDC panel. Any Powertrain Control Module (PCM) or Body Control Module (BCM) Diagnostic Trouble Codes which may be present will be displayed on the FDC panel. Codes will be stored in memory as either history or current codes. Any PCM history codes will appear first preceded by ..E. Any PCM current codes will then be displayed preceded by E.E. The same sequence will follow for any BCM codes. BCM codes will follow ..F and F.F readouts for history and current codes respectively. Record all codes on the repair order for use in diagnosing other possible customer service needs.

- After all Trouble Codes have been displayed .7.0 will display.

- When .7.0 appears on the FDC, press the "LO" button on the ECC panel to access PCM data. E.9.0 will display. Press the "LO" button again and P.2.5 will display. The PROM ID number will be displayed as a three digit code following P.2.5. Record PROM ID number on the repair order.

B. All 1991-1993 model E/K (Except 1993 model ETC, STS, Eldorado Sport Coupe) and 1994-1995 model Ksp. Note that DeVille Concours is not included.

- Observe the Driver Information Centre (DIC). All history or current Powertrain Control Module (PCM), Instrument Panel Cluster (IPC), Air Conditioning Programmer (ACP), Supplemental Inflatable Restraint (SIR) and Traction Control System (TCS) codes which are present will be displayed in that order, followed by PCM?. Record all codes on the repair order for use in diagnosing other possible customer service needs. After PCM? is displayed, press "HI" to access PCM DATA?. Press "HI" again to enter PCM parameters and PDOI will display. Press "LO" and PD99 will display preceded by the 3 or 4 digit PROM ID number. Record PROM ID number on the repair order.

Notice: On 1991 and 1992 model vehicles only, if the PROM ID is the number listed in Table 1 of this bulletin, or a lower number, the Mem-Cal should NOT be replaced. Proceed to Step 19.

2. After determining the PROM ID number of the Mem-Cal which is currently installed in the vehicle, refer to Table 2 of this bulletin. Find the model year, carline and emission system of the vehicle being serviced. Identify the old PROM ID number as recorded on the repair order. Determine the new PROM ID number and Mem-Cal part number to be installed in the PCM as indicated on the right side of the table.

CAUTION:

To prevent internal PCM damage, the ignition must be "off" when disconnecting or reconnecting power to the PCM.

The Mem-Cal and PCM are sensitive to electrostatic discharge. Follow these procedures before handling these components to reduce any possible electrostatic charge build up on the technician's body and inadvertent discharge to the electronic part:

a. Always touch a known good ground before handling these components. This should be repeated while handling the part and more frequently after sliding across a seat, sitting down from a standing position or walking a distance.

b. Avoid touching the electrical terminals of the part unless instructed to do so by a written diagnostic procedure.

c. Do not remove a part from its protective package until it is time to install it.

d. Before removing the part from its package, ground the package to a known good ground on the vehicle.

Mem-Cal/PROM Removal --------------------

Before proceeding to Step 3, determine the AM and FM radio station frequencies which have been pre-set by the customer. Write them on the repair order. The battery electrical disconnect will result in loss of both clock time and all pre-set radio stations. Resetting the clock to the correct time and the radio to the customer's preferred stations before returning the vehicle is a courtesy which will be sincerely appreciated.

3. Turn ignition key to "OFF" position and disconnect the negative battery cable.

4. Remove right hand hush panel.

5. Remove the three (3) electrical connectors to PCM.

6. Remove PCM retaining nut.

7. Pull PCM rearward to disengage the top mounting pins and remove the PCM from the passenger compartment.

8. Remove Mem-Cal access cover from the PCM and remove Mem-Cal. When removing the Mem-Cal use two fingers and push both retaining clips from the Mem-Cal at the same time. Grasp the Mem-Cal at both ends and lift from the Mem-Cal socket.

Mem-Cal Installation

9. Align the notches on the Mem-Cal with the notches in the Mem-Cal socket. Gently press on the ends of the Mem-Cal until it is seated in the socket. Do not press on the middle of the Mem-Cal. Push the clips onto the sides of the Mem-Cal until they snap into place. Listen for the click from each end.

10. Install the Mem-Cal access cover onto the PCM.

11. Place the PCM onto the mounting bracket, slide the PCM forward to engage the top mounting pins and install the PCM retaining nut.

12. Install the three (3) electrical connectors to the PCM.

13. Reconnect negative battery cable.

14. Start the engine. Engine should start and run. Tum engine off.

- Functionally check the PCM/Mem-Cal by turning the ignition to "RUN" and enter diagnostics as described in Step 1. Code E52 and B552 (1991 model E/K and 1991-1993 model C only) or Codes P052 HISTORY and 1052 HISTORY (1992-1993 model E/K and 1994-1995 model Ksp only) will appear and must be cleared.

- Clear code E52 by pressing "OFF" and "HI" simultaneously. Press any ECC panel button to exit diagnostics. If diagnostic Code F32 or B334 or I034 appears on the display, the Mem-Cal is not fully seated or is malfunctioning. If it is necessary to remove and reinstall the Mem-Cal, follow the procedures listed in Steps 3 through 14.

- To clear codes P052 HISTORY and 1052 HISTORY wait until PCM? displays. After PCM? is displayed press "HI". PCM DATA? should display. If PCM DATA? is not accessible or a NO PCM DATA message is displayed, verify that the PCM contains the correct PROM, that the PCM connectors are correctly installed, and the PCM fuses in the engine compartment fuse block are present and not blown (see page 8A-20-0 in the appropriate Service Information Manual). Press "LO" four times until PCM CLEAR CODES displays. Press "HI" to clear all PCM codes. Press "LO" twice to display IPC?. Press "HI" to display IPC DATA? followed by "LO" three times to display IPC CLEAR CODES?. Press "HI" to clear all IPC codes. Press "DEFOG" to exit diagnostics.

15. Once engine operation is verified, perform the following TPS/Idle Learn Procedure. Note that in order to perform this procedure the outside temperature must be above 10 degrees Celsius (50 degrees Fahrenheit) to enable A/C compressor operation and the engine coolant temperature must be above 80 degrees Celsius (176 degrees Fahrenheit) to ensure PCM closed loop operation. Check engine coolant temperature as follows:

A. All 1991-1993 model C

- Enter diagnostics by simultaneously pressing the "OFF" and "WARMER" buttons on the ECC panel. After .7.0 displays on the FDC panel press the "LO" button to display E.9.0. Press "HI" four times to display P.O.4 which will be followed by the coolant temperature displayed in degrees Celsius.

B. All 1994-1995 model Ksp

- Enter diagnostics by simultaneously pressing the "OFF" and "WARMER" buttons on the ECC panel. When PCM? displays on the DIC panel, press "HI" to display PCM DATA?. Press "HI" four more times to display P.O.4 which will be followed by the coolant temperature displayed in degrees Celsius.

C. All 1991-1993 model E/K

- Coolant temperature, in degrees Fahrenheit, may be displayed on the DIC by pressing and releasing the "ENG DATA" (1991 model E/K) or "INFORMATION" (I 992-1993 model E/K) button until it appears.

TPS/Idle Learn Procedure ------------------------

a. Starting from the ignition "OFF" position, wait a minimum of 20 seconds then turn the ignition to the "RUN" position (engine not running).

b. Enter diagnostics by simultaneously pressing the "OFF" and "WARMER" buttons on the Electronic Climate Control (ECC) panel.

c. Turn the ignition to the "OFF" position.

d. Wait a minimum of 20 seconds then turn the ignition to the "RUN" position (engine not running).

e. Enter diagnostics by simultaneously pressing the "OFF" and "WARMER" buttons on the ECC panel.

f. Turn the ignition to the "OFF" position.

g. Wait a minimum of 20 seconds then start engine.

h. With the engine running, apply brakes and place transaxle in "DRIVE" range.

i. Turn the ECC to "OFF" and allow the engine to idle for at least one minute (foot off the accelerator).

j. Turn the ECC to "AUTO" and verify that A/C compressor engagement occurs. Allow engine to idle for at least one minute (foot off the accelerator).

k. Place transaxle in "PARK" range and turn engine off.

16. Install hush panel.

17. Destroy the Mem-Cal removed from the vehicle by crushing it in a vise or press. Wear safety goggles or other protective eyewear when performing this procedure.

18. Reset the clock to the correct time and the AM and FM radio stations to those which were previously set by the customer.

19. Install Campaign Identification Label.

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 the five (5) digit dealer code of the dealer performing the campaign service. This information may be inserted with a typewriter or a ball point pen.

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 by the customer for periodic servicing. Additional Campaign Identification Labels can be obtained from DGN by calling 1-800-668-5539 (Monday-Friday, 8:00 a.m. to 5:00 p.m. EST). Ask for Item Number GMP 91 when ordering.

Apply the "Campaign Identification Label" only on a clean, dry surface.

CLAIM INFORMATION

Submit a Product Campaign Claim with the information indicated below:

REPAIR PERFORMED PART FAILED PARTS LABOUR COUNT PART NO. ALLOW CC-FC 0P HOURS ------------------- ----- -------- ----- ----- ------ ----- Inspect Only -- -- -- MA-96 V9924 0.2 * 1991 & 1992 C/E/K Mem-Cal Replacement Not Required

Inspect/Repair 1 ** *** MA-96 V9925 0.6 * 1992 C Mem-Cal Replacement Required

Add: 1991 C/E/K 0.1

Add: 1992 E/K 0.1

Repair Only 1 ** *** MA-96 V9926 0.5* 1995 DeVille Mem-Cal Replacement Required

Add: 1992 C 0.1

Add: 1992 E/K 0.2

Add: 1993 C/E/K 0.1

Add: 1994 DeVille 0.1

* For Campaign Administrative Allowance, add 0. 1 hours to the "Labour Hours".

** Use applicable part number as indicated in Table 2 of this bulletin (see "OLD MEMCAL PART NUMBER" colunm).

*** The "Parts Allowance" should be the sum total of the current GMSPO Dealer Net price plus 40% for 1994 and 1995 model or 30% for 1991-1993 model of all parts required for the repair.

Refer to the General Motors Claims Processing Manual for details on Product Campaign Claim Submission.

September 1996

Dear General Motors Customer:

General Motors of Canada Limited has determined that 1991-1995 model Cadillacs equipped with 4.9 liter engines may require modifications in order to help reduce emissions of carbon monoxide and hydrocarbons.

In October 1991, General Motors implemented a change in its production of 1992 model Cadillacs equipped with 4.9 liter engines that introduced an enrichment calibration to the fueling strategy. This calibration was subsequently included in production of 1993-1995 model Cadillacs equipped with 4.9 liter engines and in service parts received by certain 1991-1992 model Cadillacs equipped with 4.9 liter engines. It has been alleged that this calibration has a detrimental effect on a vehicle's emission control system and that this calibration was not adequately reported to the U.S. Government.

General Motors of Canada Limited has agreed to modify the fueling calibration for these vehicles in a way that reduces the emission of air pollutants from the vehicles without compromising driveability. All vehicles that were built with the fueling calibration in question or which subsequently received the calibration through a vehicle service repair are being recalled to have the fueling calibration revised.

To correct this condition, your GM dealer will inspect and, if necessary, replace the calibration chip in the Powertrain Control Module on your vehicle. This service will be performed at no cost to you.

Please contact your GM dealer as soon as possible to arrange a service date.

If parts are required, ask your dealer for details regarding their availability. If parts are not in stock, they can be ordered before scheduling your service date.

This letter identifies your vehicle. Presentation of this letter to your dealer will assist their Service personnel in completing the necessary correction to your vehicle in the shortest possible time.

To ensure your full protection under the emission warranty applicable to your vehicle, and your right to participate in future emission recalls, it is recommended that you have your vehicle serviced as soon as possible. Failure to do so could legally be determined to be lack of proper maintenance of your vehicle. Also, your vehicle may fail a provincial or local emission inspection test if the recall work is not accomplished.

Should your dealer find that your emission system has been intentionally disabled, you will be asked if you wish the system to be restored so that it will function as designed. The cost of such restoration will be your responsibility.

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

Customer Support Department General Motors of Canada Limit


Object Number: 169182  Size: FS


Object Number: 169183  Size: FS


Object Number: 169184  Size: FS

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.