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Operation







OPERATION

The memory system indicator gives an indication to the vehicle operator of the system status or when the system has been automatically disabled. This indicator is controlled by the instrument cluster logic circuit based upon cluster programming and electronic messages received over the Controller Area Network (CAN) data bus from the Memory Seat Module (MSM).

The memory system indicator function of the reconfigurable dot matrix Organic Light Emitting Diode (OLED) display unit is completely controlled by the instrument cluster logic circuit, and that logic will only allow this indicator to operate when the instrument cluster receives a battery current input on the fused ignition switch output (run-start) circuit. Therefore, the OLED memory system indications will always be OFF when the ignition switch is in any position except ON or START. The instrument cluster will turn ON the memory system indicator for the following reasons:

- Memory Set Message - Each time the cluster receives an electronic memory set message from the MSM, the appropriate MEMORY #1 POSITIONS SET or MEMORY #2 POSITIONS SET textual message is displayed. The message is displayed until the cluster arbitrator logic determines that another display request has priority, or until the ignition switch is turned to the OFF position, whichever occurs first.
- Memory Recall Message - Each time the cluster receives an electronic memory recall message from the MSM, the appropriate DRIVER 1 MEMORY or DRIVER 2 MEMORY textual message is displayed. The message is displayed until the cluster arbitrator logic determines that another display request has priority, or until the ignition switch is turned to the OFF position, whichever occurs first.
- Seatbelt Buckled Message - Each time the cluster receives an electronic seatbelt buckled memory system lockout message from the MSM, the MEMORY SYSTEM DISABLED and SEATBELT BUCKLED textual messages and icon are cycled. The two parts of the message are cycled about every three seconds until the MSM sends an electronic message to cancel the memory system lockout event, until the cluster arbitrator logic determines that another display request has priority, or until the ignition switch is turned to the OFF position, whichever occurs first.
- Vehicle Not In Park Message - Each time the cluster receives an electronic vehicle not in Park memory system lockout message from the MSM, the MEMORY SYSTEM DISABLED and VEHICLE NOT IN PARK textual messages are cycled. The two parts of the message are cycled about every three seconds until the MSM sends an electronic message to cancel the memory system lockout event, until the cluster programming or another request requires a different OLED display, or until the ignition switch is turned to the OFF position, whichever occurs first.

The MSM continually monitors inputs from the seatbelt switch through the ElectroMechanical Instrument Cluster (EMIC) (also known as the Cab Compartment Node/CCN), the Driver Door Module (DDM), the Wireless Ignition Node (WIN) (also known as the Sentry Key Immobilizer Module/SKIM, the Sentry Key REmote Entry Module/SKREEM or the Wireless Control Module/WCM), the Powertrain Control Module (PCM) and, if equipped, the Transmission Control Module (TCM) to determine the proper outputs to the memory system components. The MSM then sends the proper lamp-ON or lamp-OFF message to the EMIC.

For proper diagnosis of the memory system, the MSM, the EMIC, the CAN data bus or the electronic communication related to memory system indicator operation a diagnostic scan tool is required. Refer to the appropriate diagnostic information.