1997-2001 Lexus GS 300, GS 400 Air Conditioning System Service Manual (P/N C4085-91017)

• Official Lexus publication RM718U, 2000 edition (P/N C4085-91017).
• 100-page factory reference detailing the 1997–2001 Lexus GS 300 and GS 400 air conditioning and heating systems.
• Provides precise fluid capacities, fastener torque values, and sensor test parameters for the climate control suite.
• Features 12 exploded-view component diagrams with torque specifications, 6 electrical test parameter tables, and 9 diagnostic symptom charts for system troubleshooting.

System Layout and Documentation

The documentation breaks down the climate control and floor-shift systems into modular sections. You will find detailed component-level images identifying mounting hardware and service connections for the refrigerant lines, evaporator unit, condenser assembly, and blower motor. It outlines the factory-approved procedural steps for discharging, evacuating, and charging the refrigeration system. The manual also reviews the removal and reassembly order for the instrument panel, console box, and air ducts.

Specifications and Diagnostic Data

Having exact technical data is critical for component verification and system testing. Working with pressurized refrigerants requires strict adherence to safety protocols and professional equipment to prevent severe injury or system damage. This manual documents the system refrigerant volume at 600 ± 50 grams. Assembly data specifies the expansion valve to evaporator connection at 4.1 Nm, while compressor mounting hardware requires 10 Nm for a secure fit. You can verify the magnetic clutch clearance at 0.5 ± 0.15 mm, with shims available for adjustment. Diagnostic tables list the compressor lock sensor resistance at 570–1,050 ohms at 20°C. These factory parameters give technicians the exact baselines needed for accurate troubleshooting.