Operation - Power Seat System

2004 Toyota Matrix XR, FWD, StandardSECTION Operation - Power Seat System
WARNING: This page is about a different car, the 2004 Chrysler Pacifica. However, it is still accessible from the selected car via links, so may be relevant.

The power seat system receives battery current through a circuit breaker, located in the Integrated Power Module. The power seat system is designed to function regardless of the ignition switch position.

A low-voltage cut-off feature is designed into the power seat system. If the vehicle battery voltage drops below a certain set-point (approx. 11.5v), the power seats will not operate. This is necessary to prevent the vehicles battery from being discharged to the point that the vehicle may not start and run. Under normal conditions this feature will be transparent.

When a power seat switch control knob(s) is actuated, a hard-wired resistance signal is sent to the appropriate door module. The door module then sends the request to the Memory Heated Seat Adjustable Pedal Module (MHSAPM) via the PCI data bus circuit. The MHSAPM is responsible for controlling the 12v battery feed and ground path to the selected seat track motor to move the adjuster through its drive unit until the switch is released, or until the travel limit of the adjuster is reached. The Memory Heated Seat Adjustable Pedal Module (MHSAPM) is the main control module for the power, memory and heated seat systems. The module will drive a maximum of 2 motors at a time in a given direction.

No power seat switch should be held applied in any direction after the seat track has reached its travel limit. The power seat track motors each contain a self-resetting circuit breaker to protect them from overload. However, consecutive or frequent resetting of the circuit breaker must not be allowed to continue, or the motor may be damaged. Refer to the owner's manual in the vehicle glove box for more information on the features, use and operation of the power seat system.

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