P0063: O2 Sensor Heater Control Circuit Low — Bank 2 Sensor 3
What to do
No driveability impact. Fix before an emissions test.
What this code means
The bank 2 third sensor heater circuit is reading low, typically a short to ground somewhere along its long underfloor run. Physical inspection of the harness usually finds this faster than electrical testing does.
Likely causes
Start here
- Wiring shorted to ground · moderate
- Road damage to underfloor wiring · moderate
- Failed oxygen sensor heater element · easy
Less common
- Corroded or loose connector · easy
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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