2003 Saturn Ion 1 AutomaticFACTORY OEM SERVICE PROCEDURE

Control Units

CONTROL UNITS LOCATION

Component Location
Body Control Module At lower center of instrument panel. See Figure.
Cruise Control Module Behind lower left side of dash, above brake pedal.
Electronic Brake Control Module At left side of engine compartment. See Figure.
Engine Control Module At left side of engine compartment. See Figure.
Ignition Control Module At top rear of engine, near oil fill cap. See Figure.
Inflatable Restraint Roof Rail Module (ASF) (Left) At left rear side of roof bracket, in "C" pillar.
Inflatable Restraint Roof Rail Module (ASF) (Right) At right rear side of roof bracket, in "C" pillar.
Inflatable Restraint Sensing & Diagnostic Module Under center console, behind emergency brake.
Sun Roof Module Left of sun visor, in headliner.
Transmission Control Module At left rear of engine compartment, near strut tower. See Figure.
Vehicle Communication Interface Module At center of rear package shelf, between rear speakers.
Factory Service Tools

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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.