Lexus ES: System Description
SYSTEM DESCRIPTION
HEATED STEERING WHEEL SYSTEM
(a) The heated steering wheel system heats the steering wheel assembly when the system is turned on using the steering wheel heater switch (refreshing seat switch) or steering wheel heater switch (multi-display assembly).
(b) The heated steering wheel system uses a thermistor inside of the steering wheel assembly to detect the heater temperature and maintain the set temperature.
(c) When the automatic steering wheel heater is set to on, the external and internal temperature is detected and an automatic judgment control heats the steering wheel automatically when the engine switch is turned on (IG).
HEATER CONTROLLER SYSTEM
(a) Operation description
(1) When the engine switch is on (IG) and the system is turned on using the steering wheel heater switch (refreshing seat switch) or steering wheel heater switch (multi-display assembly), the indicator illuminates and the steering wheel heater control assembly supplies operating current to the steering wheel heater unit.
When the system is turned off using the steering wheel heater switch (refreshing seat switch) or steering wheel heater switch (multi-display assembly), the indicator turns off and the steering wheel heater control assembly stops supplying operating current to the steering wheel heater unit.
(2) A thermostat is installed in the steering wheel heater unit as a safety mechanism.
(3) Heated steering wheel controller (steering vibration ECU) has diagnosis function, refer to the fail-safe chart.
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(b) Signal input / output description
| Signal | Signal Name | Function |
|---|---|---|
| Input | Thermistor input | Input of voltage corresponding to heater temperature |
| Input | Heater operation signal | Input of steering wheel heater operation signal |
| Output | Operation condition output | Outputs steering wheel heater operation condition. |
| Output | Operating current output | Outputs operating current of steering wheel heater unit. |
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How To Proceed With Troubleshooting
CAUTION / NOTICE / HINT HINT:
Use these procedures to troubleshoot the heated steering wheel system.
*: Use the Techstream.
PROCEDURE 1. VEHICLE BROUGHT TO WORKSHOP
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Customize Parameters
CUSTOMIZE PARAMETERS CUSTOMIZE HEATED STEERING WHEEL SYSTEM (a) Customizing with the Techstream. NOTICE:
When the customer requests a change in a function, first make sure that the function can be
Problem Symptoms Table
PROBLEM SYMPTOMS TABLE HINT: Use the table below to help determine the cause of problem symptoms. If multiple suspected areas are listed, the potential causes of the symptoms are listed in order of pr
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Microphone Circuit
DESCRIPTION
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Using this circuit, the radio receiver assembly sends power to the telephone microphone assembly, and the telephone microphone assembly s
Terminals Of Ecu
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