Back to 2003 Mazda B2300

2003 MAZDA B2300

2.3L I4FWDAUTOMATICgas
Repairs0Labor471Torque2462Fluid6DTC713Battery0Maintenance0Recalls0
P0161low severityPowertrain

O2 Sensor Heater Circuit Bank 2 Sensor 2

on 2003 Mazda B2300 2.3L I4 · FWD

What this code means

Malfunction in the downstream O2 sensor heater on Bank 2.

Symptoms

  • Check Engine Light
  • Failed emissions

Common causes

  • Faulty heater
  • Blown fuse
  • Wiring issue

Diagnostic steps

  1. Check fuse
  2. Test heater resistance
  3. Inspect wiring

Repair notes

Replace sensor.

Other Powertrain codes on this vehicle

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