1993 Subaru Justy BaseFACTORY OEM SERVICE PROCEDURE

Code 32: Oxygen Sensor

NOTE: Refer to illustration for ECU connector and terminal identification. See Figure .
  1. Start engine. With engine idling, measure voltage between ground and ECU connector F121, terminal No. 4 (backprobe). If voltage fluctuates between 0.1 and 1 volt, check for poor ECU connector contact. Repair connector and/or wiring harness as necessary. If voltage does not fluctuate between 0.1 and 1 volt, go to next step.
  2. Start engine. Ensure engine is at normal operating temperature. Disconnect oxygen sensor. Measure voltage between ground and oxygen sensor terminal. If voltage is about 0.5 volt, go to next step. If voltage is not about 0.5 volt, replace oxygen sensor.
  3. Disconnect ECU connectors. Measure resistance between ECU connector F121, terminal No. 4 and oxygen sensor connector (wiring harness side). If resistance is less than one ohm, check for poor ECU connector contact. Repair connector and/or wiring harness as necessary. If connector and wiring harness are okay, replace ECU. If resistance is more than one ohm, repair connector and/or wiring harness as necessary.
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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.