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2003 Toyota Matrix Oxygen Sensor Problem

Engine light was on and computer determined that a malfunction existed in the heater circuit for oxygen sensor 1

Is this powertrain issue? Should the 5-year powertrain warranty cover?

How to determine whether the entire sensor should be replaced or just to fix the fuse?


The PCM has determined that a malfunction exists in the heater circuit for oxygen sensor 1 in bank 1. (Oxygen sensor 1 is closest to the cylinder head before the catalytic converter, while oxyen sensors 2 & 3 are located further downstream and are typically mounted in or after the catalytic converter) (bank 1 identifies the location of cylinder #1, while bank 2 identifies the cylinders on the opposite bank)

Definition
HO2S 11 Heater condition (Heated Oxygen Sensor Bank 1 Sensor 1)

Explanation
The powertrain control module monitors the oxygen sensor heater. The
computer has recongnized as failure in this circuit.

Probable Causes
1. Oxygen sensor defective
2. Poor connection at oxygen sensor
3. Check circuit fuse  

More than likely the o2 sensor.Toyota had problems with them in the tundra`s not sure about the matrix so I would call toyota first.