Emissions

P0061 — O2 Sensor Heater Resistance (Bank 2, Sensor 3)

Severity: low Safe to drive

What P0061 means

The engine control unit monitors the heater circuit of the bank 2, sensor 3 oxygen sensor, usually located after the catalytic converter. The heater brings the sensor up to operating temperature quickly so it can read exhaust oxygen accurately. P0061 sets when the heater circuit's resistance or current falls outside the expected range.

Symptoms

  • Check engine light on
  • Engine usually runs normally
  • Possible slight increase in fuel consumption
  • Possible higher exhaust emissions
  • Failed emissions inspection

Possible causes

  1. Failed heater element inside the oxygen sensor
  2. Damaged wiring or connector in the heater circuit (open, corroded, shorted to ground)
  3. Blown fuse or missing power supply to the heater
  4. Exhaust leak near the sensor affecting its operation
  5. Faulty PCM or heater driver (rare)

How to diagnose

  1. Scan for codes and freeze frame data, and look for other oxygen sensor codes
  2. Inspect the sensor wiring and connector for chafing, heat damage and corrosion
  3. Check the heater fuse and relay using the vehicle wiring diagram
  4. Measure heater resistance at the sensor terminals and compare to the spec
  5. Check for power and the control signal at the connector with the ignition on
  6. Test the circuit for opens and shorts to ground between the sensor and PCM
  7. Look for exhaust leaks near the sensor
  8. Clear the code after repair and confirm it does not return

Common fixes

  • Replace the bank 2, sensor 3 oxygen sensor
  • Repair the damaged wiring or connector
  • Replace the blown fuse and find why it failed
  • Repair the heater power supply circuit
  • Replace or reflash the PCM (very rare)

Questions and answers

Can I drive with a P0061 code?

Usually yes, as it does not directly threaten the engine. Still, repair it soon to avoid emissions problems and a failed inspection.

What does bank 2 sensor 3 mean?

Bank 2 is the side of the engine that does not contain cylinder 1. Sensor 3 is typically downstream of the catalytic converter, though the exact location varies by vehicle.

This is general information about the code. The meaning can differ between makes and models: a scan tool and the repair manual for your car will show the exact cause.