P0147: O2 Sensor Heater Circuit — Bank 1 Sensor 3
What to do
No driveability impact. Blocks emissions readiness until repaired.
What this code means
A heater circuit fault on the bank 1 third sensor, overlapping with P0042. Exhaust gas is coolest at this point in the system, so the heater matters more here than anywhere else — without it the sensor may never reach operating temperature on short journeys.
Likely causes
Start here
- Failed oxygen sensor heater element · easy
- Corroded or loose connector · easy
- Road damage to underfloor wiring · moderate
Less common
Symptoms
Components involved
Information, not instruction
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Have anything you intend to act on checked by a trained person against the manufacturer's own procedure for your vehicle. Nothing here replaces that procedure.
Community experience
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What makes one worth reading:
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