Memory Power Seat Inoperative (Replace Memory Seat Module with New Design Module)

This bulletin is being revised to update the Parts and Warranty Information. Please discard Corporate Bulletin Number 01-08-50-011 (Section 08 - Body and Accessories).

Some customers may comment that the memory seats or heated seats are inoperative.

A logic lock-up of the memory seat module may cause this condition.

Important: This repair is not to be performed on vehicles without memory/heated seats. In the event a vehicle without memory/heated seats has an inoperative power seat, use published Service Information for diagnosis.

Diagnosis

If the seat is currently inoperable, perform the following diagnosis in order to determine if this correction is the correct repair.

1. Connect the Tech 2 to the vehicle.
2. When the main menu is displayed on the Tech 2, verify the software version that is installed in the Tech 2. If it is not software version 21.007 or later which was broadcast to dealerships on August 20, 2001, or CD received August 27, 2001, update the Tech 2.
3. Select Diagnostics. Press Enter.
4. Select model year 2002. Press Enter.
5. Select LD TRK, MPV, Incomplete. Press Enter.
6. Select Body. Press Enter.
7. Select LD Truck line "S" or "T". Press Enter.
8. Select Body Type. Press Enter.
9. Select Air Conditioning Type. Press Enter.
10. Select Driver Seat Module. Press Enter.
11. Select Data Display. Press Enter.
12. Select Input/Output. Press Enter.
13. If the Tech 2 does not communicate with the driver seat module ("No Communications with Vehicle Check Diagnostic Link Connector Check Ignition (On/Off)"), the module is possibly locked due to a logic lockup. Remove the LGM/DSM (Lift Glass Module/Driver Seat Module) fuse. This fuse is also the fuse for the Passenger Seat Module; 10 AMP, fuse #6 from the Rear Underseat Fuse Block.
14. Verify that the fuse is not open. If OK, wait 30 seconds before reinstalling the fuse.
15. Attempt to move the seat. If the seat now moves or the Tech 2 now establishes communication with the driver seat module, you should replace the seat module using the procedure below. If not, use normal SI service diagnostics to determine why the seat is inoperable.

Memory/Heated Seat Module Replacement

Replace the memory/heated seat module using the procedure listed below.

1. Position the driver's front seat in the full up-right position.

If the seats are inoperative, you may be able to re-initialize the seat module by disconnecting the seat module wiring harness from the seat module at the front edge of the seat cushion for 30  seconds.

2. Remove the three screws that attach the seat switch bezel to the seat cushion assembly and set aside.
3. Remove the four nuts that attach the seat cushion pan to the seat assembly.
4. Remove the production aid seat clip from the front outboard stud and discard (if equipped).
5. Position the seat pan to access the seat module retaining screw and remove the screw.
6. Disconnect the electrical connectors from the seat module.
7. Connect the electrical connectors to the new seat module.
8. Reinstall the seat module retaining screw.

Tighten
Tighten the screw to 3 N·m(26 lb in).

9. Position the seat pan to the seat assembly and install the four retaining nuts.

Tighten
Tighten the nuts to 25 N·m(18 lb ft).

10. Reposition the seat switch bezel and install the three retaining screws.

Tighten
Tighten the screws to 3 N·m(26 lb in).

11. Lower the seat to the normal position.
12. If the vehicle is equipped with heated seats, perform all steps on the front passenger side seat as well.

Parts are currently available from GMSPO.

For vehicles repaired under warranty, use: