1990 Mazda B2600i Base, 2D PickupFACTORY OEM SERVICE PROCEDURE

Code 15: O2 Sensor

Is O2 sensor output voltage okay? See PIN VOLTAGE CHART S and SENSOR RANGE CHARTS article. If not within specifications, replace O2 sensor. If output voltage is not within specifications, is sensitivity of O2 sensor okay? If not replace O2 sensor. If sensitivity is okay, perform after procedure.

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:

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