CAMPAIGN: PARKING BREAK SOLEOID VALVE MALFUNCTION. GMC Truck GMC MD Conventional (C Model) 1996

SUBJECT: PARKING BRAKE SOLENOID VALVE MALFUNCTION ----------------------------------------

Models: 1996 GMC TopKick With Auto-Apply Park Brake Systems (J7l) ----------------------------------------------------------

TO: ALL GENERAL MOTORS DEALERS

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General Motors of Canada Limited has decided that a defect which relates to motor vehicle safety exists in certain 1996 GMC TopKick model medium duty conventional vehicles equipped with auto-apply park brakes. These vehicles may exhibit an intermittent inoperative park brake apply under certain conditions. If the park brake does not apply (manual or auto application), the "Service Park Brake" warning light will illuminate. However, if the warning light goes unnoticed and the operator exits the vehicle, the vehicle could roll away and a vehicle crash could occur without prior warning.

To correct this condition, dealers are to replace the parking brake solenoid valve with one having a 12 volt coil and the original valve spring.

VEHICLES INVOLVED:

Involved are the following nine (9) 1996 GMC TopKick model medium duty conventional vehicles equipped with auto-apply park brakes (RPO J71):

VIN VIN VIN --- --- ---

1GDE6H1J4TJ510646 1GDJ6H1J3TJS12709 1GDL7H1J3TJ512831 1GDG6H1MOTJ514115 1GDJ6H1J6TJ514132 1GDL7H1M2TJ513740 1GDJ6H1J2TJS12751 1GDL7H1J3TJ512635 1GDL7H1M7TJ514026

NOTE: PLEASE CHECK DCS SCREEN 445 OR YOUR V.I.N. LISTING BEFORE PERFORMING CAMPAIGN TO ENSURE THAT THE VEHICLE IS AFFECTED. ONLY AFFECTED VINS WILL BE PAID.

All affected vehicles have been identified by the VIN listing provided to involved dealers with this bulletin. Any dealer not receiving a listing was not shipped any of the affected vehicles.

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 owners take possession of these vehicles.

Dealers are to perform this campaign on all involved vehicles at no charge to owners, regardless of kilometres traveled, age of vehicle, or ownership, from this time forward.

Owners of vehicles recently sold from your new vehicle inventory with no owner information indicated on the dealer listing, are to be contacted by the dealer, and arrangements made to make the required correction according to instructions contained in this bulletin. This could be done by mailing to such owners a copy of the owner letter accompanying this bulletin. Campaign follow-up cards should not be used for this purpose, since the owner may not as yet have received the notification letter.

In summary, whenever a vehicle subject to this campaign is taken into your new or used 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.

CAMPAIGN PROCEDURE:

Refer to Section 4 of the Service Policies and Procedures Manual for the detailed procedure on handling Product Campaigns. Dealers are requested to complete the campaign on all transfers as soon as possible.

OWNER NOTIFICATION:

All owners 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 owner letter included with this bulletin). The listings provided are for campaign activity only and should not be used for any other purpose.

PARTS INFORMATION:

Parts required to complete this campaign should be ordered through regular channels, as follows:

Part Number Description Quantity/Vehicle ----------- ----------- ----------------

15687353 Parking Brake Solenoid Valve Assembly 1

PARTS AND LABOUR CLAIM INFORMATION:

Credit for the campaign work performed will be paid upon receipt of a properly completed campaign claim card or DCS transmission in accordance with the following:

Repair Code Description Time Allowance ----------- ----------- --------------

2A Remove and Install Parking Brake 0.7 Valve Assembly

Time allowance includes 0.1 hour for dealer administrative detail associated with this campaign. Parts credit will be based on dealer net plus appropriate model year parts handling allowance.

SERVICE PROCEDURE:

REFER TO FIGURE 1

1. Chock the wheels and follow all safety related precautions.

2. Disconnect the negative battery cable.

3. Remove the cover from the compartment box on the driver's side of the truck.

4. Locate the parking brake solenoid valve assembly in the compartment box near the left rear corner of the box.

CAUTION:

The solenoid may be extremely hot. Use caution when handling the solenoid and/or solenoid valve assembly.

5. Disconnect the parking brake solenoid coil electrical connector.

6. Position a drain pan under the work area to catch any droplets of fluid that may leak out.

7. Disconnect the two hydraulic pipe assembly fittings attached to the parking brake valve assembly.

8. Remove two parking brake solenoid. valve mounting nuts atem 6) four washers (Items 2 and 7) and two bolts (Item 1) located near the bottom of the valve assembly.

9. Remove the solenoid valve assembly (Item 4).

10. Remove the nut (Item A) and metal label and solenoid coil (Item B) from the top of the valve assembly (Item C). Retain the 12-volt black solenoid coil. Remove and retain the fittings from the valve assembly. Note orientation of the fittings. Discard valve.

11. PENSKE VEHICLES ONLY: Remove the nut from the replacement valve. Proceed to Step 13.

12. ALL OTHER VEHICLES: It is necessary to remove and discard the 10-volt solenoid coil on the replacement assembly. 12-volt solenoid coils must be used on all vehicles.

Remove the nut (Item A) and metal label and solenoid coil (Item B) from the top of the replacement valve assembly Item C). Discard the 10-volt black solenoid coil. Proceed to Step 13.

13. Install the removed 12-volt solenoid coil on the replacement valve. Install the metal label and nut Torque the nut (Item A) to 5-8 N.m maximum (4-6 lb. ft.).

NOTICE: Voltage identification is stamped on the bottom of the solenoid coil. The replacement part from GMSPO will include a 10-volt solenoid coil. The 10-volt solenoid coil MUST be removed and discarded. The 12-volt coil MUST be installed on the replacement valve assembly.

CAUTION:

Over-tightening the nut may cause valve failure.

14. Install fittings on replacement valve assembly in the correct position. Reinstall the valve assembly on the vehicle. Torque the mounting nuts (Item 6) to 13 N.m (115 lb. in).

15. Reconnect the hydraulic pipe assemblies. Torque the pipe fittings to 16 N.m (12 lb. ft).

16. Reconnect the parking brake solenoid coil electrical connector.

17. Reconnect the negative battery cable.

18. Cycle the parking brake system several times. Check for leaks.

19. Clear any Diagnostic Trouble Codes that may have been set in the Module Assembly. For displaying and clearing diagnostic trouble codes refer to the 1996 Medium Duty Truck Service Manual, Book 1 of 2, Section Electric/Hydraulic Parking Brake, Page 5FI-5.

20. Check for proper operation of the parking brake. To apply the parking brake, start the vehicle and pull the "Park Brake" knob toward you, then shift the transmission to Neutral (N) or Park (P). To release the parking brake, press the knob in. In order to release the parking brake the ignition must be in the "RUN" position and the shift lever out of Park (P). The parking brake will apply if the ignition is turned off or if it is in Park (P). It will also apply if the vehicle's battery is dead or disconnected. The "Park Brake" light may flash while the parking brake is being released and should be on when the parking brake is applied.

CAUTION:

It may take a few seconds for the parking brake to fully apply, and even longer when it is cold outside. If you turn the ignition off before the parking brake is applied, an alarm will sound until the parking brake applies fully.

21. Reinstall the compartment box cover.

22. Remove the wheel blocks.

23. Install Campaign Identification Label.

INSTALLATION OF CAMPAIGN IDENTIFICATION LABEL

Clean surface of radiator upper mounting panel and apply a Campaign Identification Label. Make sure the correct campaign number is inserted on the label. This will indicate that the campaign has been completed.

July 1996

Dear General Motors Customer:

To correct this condition, your GM dealer will replace the parking brake solenoid valve assembly with one having a 12 volt solenoid original valve spring.

This service will be provided for you at no charge.

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.

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 Limited

Object Number: 108201 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.