OBD-II code · Powertrain (generic)

P0038 HO2S Heater Control Circuit High (Bank 1 Sensor 2)

The heater control line for the upstream bank 1 oxygen sensor reads above the expected voltage, typical of a short to supply.

Is it safe to drive with P0038?

Usually safe to drive in the short term. Get it diagnosed when convenient, sooner if the car drives differently.

Common causes

  • Most likelyHeater wire shorted to supply
  • Less likelyConnector pins corroded - high contact resistance
  • Less likelySupply wire pinched against B+ source

Repair at a glance

Difficulty
Easy
DIY friendly
Often, with basic tools
Typical labour
0.5–1.5 h
Emissions test
Likely to fail
After the fix
A drive cycle is needed before the light stays off
Parts involved
Oxygen Sensor Heater, Sensor Wiring

Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.