Climate Control Seat System (Diagnostics - Introduction): Overview Lexus LX J200

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COMMUNICATION TABLE

SYSTEM DESCRIPTION

1. GENERAL The climate control seat system creates cold or warm air to increase the comfort of seats that have become hot or cold. The air is heated or cooled by the Peltier element on the seat cushion pad and seatback. The air is then sent to the seat cushion and seatback by the blower installed under the seat. The blower is operated by pressing the climate control seat switch. The climate control seat switch has several modes that vary the quantity of air to be sent to the seat. There are 7 modes in total: 3 cooled air modes, 3 heated air modes and ventilation mode. HINT: When the highest level for cooled air operates for 15 minutes, the quantity of air falls 1 level.
2. FUNCTION OF MAIN COMPONENT Component Outline Climate Control Seat Switch Selects between modes: 3 cooled air modes, 3 heated air modes and ventilation mode. Seat Climate Control Controller (Thermistor) Detects surface temperature of seatback and seat cushion. Seat Climate Control Controller (TED) Cools and heats through function of Peltier element. Seat Climate Control Blower Provides airflow to seatback and seat cushion upon receiving instructions from climate control ECU in accordance with climate control seat switch mode. Seat Climate Control ECU Controls system based on signals from temperature sensor and climate control seat switch While system is activated, only driver side climate control ECU outputs A/C signals. Monitors output amperage of climate control blower. Front Seat Heater (Seat Cushion and Seatback) Fast acting seat heater warms seat in initial stage of heating mode. Rear Seat Heater (Seat Cushion and Seatback) Fast acting seat heater warms seat in initial stage of heating mode.
3. SYSTEM OPERATION Function Outline Driver Seat Front Passenger Seat Normal control This system operates the seat climate control blower located underneath the seat to provide airflow to the seat cushion and seatback. Airflow is warmed or cooled by the Peltier element in the seat climate control controller. The air that flows to the seat surface is distributed by passing through grooves that are provided on the seat pad surface. The air is then dissipated throughout the seat surface through slab urethane foam and is discharged through the seat cover. o o Power ON full-power control This control outputs the maximum voltage to the seat climate control controller and seat climate control blower for approximately 15 minutes only when the conditions listed below have been met: The engine switch is on (IG). After the climate control seat switch is turned on, the switch mode is subsequently turned to max warm or max cool within approximately 10 minutes. o o A/C output control The climate control seat ECU outputs an A/C signal to the A/C amplifier while it controls the climate control seat system. The climate control seat ECU sends a demand signal for A/C control to the A/C amplifier. o o

OPERATION CHECK

1. CLEAN AIR FILTER AND PERFORM DUCT INSPECTION Remove the rear seatback assembly and rear seat cushion assembly. Check if the duct of the seat climate control controller is disconnected or cracked. Clean the air filter of the seat climate control controller. HINT: The amount of air passing through the seat climate control controller (Peltier) may decrease if one of the following occurs: 1) duct disconnection; 2) duct cracks; 3) severe clogging of the air filter; or 4) deterioration of blower performance. If any of these occurs, the thermistor operates excessively, which may cause the seat to be unable to heat up or cool down properly.
2. INSPECT CLIMATE CONTROL SEAT OPERATION When the climate control seat switch is turned on, check that the seat heater and blower operate based on the seat temperature. If the seat temperature increases as a result of the seat heater operation, check that the seat heater operation stops and the blower operation continues. HINT: Based on the cabin temperature, seat temperature, etc., the seat heater operation time varies.

See also:
• Climate Control System does not Operate on Driver Side