Code result
P0043
HO2S Heater Control Circuit Low
Moderate severity
What it means
Heater control voltage of the bank 1, sensor 3 oxygen sensor is below the expected range — short to ground or low-resistance fault.
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 ground
highOne of the most commonly reported causes for this code — check this first.
Connector pins corroded - high contact resistance
lowLess common, but worth ruling out after the more likely causes.
Harness chafing through insulation
lowLess common, but worth ruling out after the more likely causes.
Related help
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