2003 Lexus RX 300 FWDFACTORY OEM SERVICE PROCEDURE

Control Units

CONTROL UNITS LOCATION

Component Component Location
ABS & BA & TRAC & VSC ECU Behind right side of dash. See Figure.
Body ECU Behind left side of dash. See Figure.
Center Air Bag Sensor Assembly Under center of dash, forward of center console. See Figure.
Combination Meter ECU Behind combination meter.
Cruise Control ECU Behind left side of dash. See Figure.
Driver Door ECU In left front door. See Figure.
Engine Control Module Behind right side of dash. See Figure.
Front Passenger Door ECU In right front door. See Figure.
Headlight Beam Level Control ECU Behind left end of dash.
Headlight ECU (Left/Right) Behind respective headlight.
Moon Roof Control ECU On front center of moon roof. See Figure.
Navigation ECU On right rear of cargo area. See Figure.
Power Seat ECU Under driver's seat.
Rear Door ECU (Left) In left rear door. See Figure.
Rear Door ECU (Right) In right rear door. See Figure.
Shift Lock ECU Under center console, beside shift lever. See Figure.
Telephone ECU On right rear of cargo area. See Figure.
Wireless Door Lock ECU In center of vehicle. See Figure.
Factory Service Tools

Use the Manual With the Right Hardware

Pair factory procedures with proven DIY tools so the instructions are easier to execute.

Disclosure: Verified tool recommendations may earn an affiliate commission at no cost to you.

Shop Manual-Ready ToolsCompare Repair QuoteQuote Shield Pro

When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • • You smell fuel, burning insulation, or see smoke.
  • • Brakes feel soft, pull hard to one side, or make grinding noises.
  • • The engine overheats, stalls repeatedly, or misfires under load.
  • • You are missing required tools, torque specs, or safe lifting equipment.
  • • You are not confident in the next step or safety outcome.