Code result

P0044

HO2S Heater Control Circuit High

Moderate severity

What it means

Heater control voltage of the bank 1, sensor 3 oxygen sensor is above the expected range — short to power or open ground.

Is it safe to drive?

Use caution

The vehicle is usually drivable for short distances, but the problem can worsen or affect emissions. Diagnose and repair as soon as practical.

Most likely causes

  • Heater wiring shorted to battery

    high

    One of the most commonly reported causes for this code — check this first.

  • Connector pins corroded - high contact resistance

    low

    Less common, but worth ruling out after the more likely causes.

  • Supply wire pinched against B+ source

    low

    Less common, but worth ruling out after the more likely causes.

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