Description - Memory System

WARNING: This page is about a different car, the 2004 Jeep Grand Cherokee. However, it is still accessible from the selected car via links, so may be relevant.

An electronic memory system is standard equipment on the Limited model. The memory system is able to store and recall the driver side power seat positions (including the power recliner position), and both outside power mirror positions for two drivers. For vehicles with a radio connected to the Programmable Communications Interface (PCI) data bus network, the memory system is also able to store and recall up to twenty - ten AM and ten FM - radio station presets for two drivers. The memory system also will store and recall the last station listened to for each driver, even if it is not one of the twenty preset stations.

The memory system will automatically return to all of these settings when the corresponding numbered and color-coded button (Driver 1 - Black, or Driver 2 - Gray) of the memory switch on the driver side front door trim panel is depressed, or when the doors are unlocked using the corresponding numbered and color-coded (Driver 1 - Black, or Driver 2 - Gray) Remote Keyless Entry (RKE) transmitter. A customer programmable feature of the memory system allows the RKE recall of memory features to be disabled in cases where there are more than two drivers of the vehicle.

The memory system also has a customer programmable easy exit feature that will move the driver seat rearward 55 millimeters (two inches) or to the end of its travel, whichever occurs first, when the key is removed from the ignition switch lock cylinder.

A Memory Seat Module (MSM) or Memory Heated Seat Module (MHSM) are used on this model to control and integrate the many electronic functions and features included in the memory system. On vehicles equipped with the heated seat system option, the MHSM also controls the functions and features of that system.

The memory system includes the following components:

Memory seat module (or memory heated seat module)
Memory switch
Position potentiometers on both outside power mirrors
Position potentiometers on the driver side power seat track and power seat recliner motors.
Radio receiver (if PCI data bus capable).

Certain functions and features of the memory system rely upon resources shared with other electronic modules in the vehicle over the Programmable Communications Interface (PCI) data bus network. The PCI data bus network allows the sharing of sensor information. This helps to reduce wire harness complexity, internal controller hardware, and component sensor current loads. At the same time, this system provides increased reliability, enhanced diagnostics, and allows the addition of many new feature capabilities. For diagnosis of these electronic modules or of the PCI data bus network, the use of a DRB(R) scan tool and the proper Diagnostic Procedures are recommended.

The other electronic modules that may affect memory system operation are as follows:

Body Control Module (BCM) - Refer to BODY CONTROL MODULE in Electronic Control Modules for more information.
Driver Door Module (DDM) - Refer to DOOR MODULE in Electronic Control Modules for more information.
Electronic Vehicle Information Center (EVIC) - Refer to ELECTRONIC VEHICLE INFO CENTER for more information.
Passenger Door Module (PDM) - Refer to DOOR MODULE in Electronic Control Modules for more information.
Powertrain Control Module (PCM) - Refer to POWERTRAIN CONTROL MODULE in Electronic Control Modules for more information.
Radio Receiver - Refer to RADIO in Audio Systems for more information.

Refer to HEATED SEAT SYSTEM for more information. Refer to DESCRIPTION - REMOTE KEYLESS ENTRY SYSTEM for more information on the RKE system. Refer to POWER MIRRORS for more information on the mirror position potentiometers. Refer to POWER SEAT TRACK and RECLINER MOTOR for more information on the driver side power seat position potentiometers.

Refer to POWER SEATS in Wiring Diagrams for complete circuit diagrams. Following are general descriptions of the remaining major components in the factory-installed memory system.