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Section 18 (Automatic A/C-Heater Systems): Description

WARNING: This page is about a different car, the 2003 Lexus ES 300 and 2002 Lexus ES 300. However, it is still accessible from the selected car via links, so may be relevant.
WARNING: To avoid injury from accidental air bag deployment, read and carefully follow all SERVICE PRECAUTIONS and DISABLING & ACTIVATING AIR BAG SYSTEM procedures in AIR BAG RESTRAINT SYSTEMS article in RESTRAINTS.
NOTE: When battery is disconnected, radio will go into anti-theft protection mode. Obtain radio anti-theft protection code from owner prior to servicing vehicle.

An Electronic Control Unit (ECU), located within A/C-heater control assembly, automatically controls all A/C and heating functions. Manual controls allow the driver to select air distribution mode and desired temperature. In addition to normal A/C system components, automatic A/C-heater system includes various motors, controls, and sensors. See Fig 1. A replaceable air filter is located in front of A/C evaporator. System has self-diagnostic capabilities.

Fig 1: Identifying Automatic A/C-Heater System Components
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