What causes a P0038 code?

P0038 can be triggered by several issues — see the verified probable causes and step-by-step diagnostics shared by mechanics and owners on OBDIY.

Can I drive with a P0038 code?

Drivability depends on the severity. Check the severity rating and verified driver reports on this page before continuing to drive with P0038 active.

Follow the step-by-step diagnostic on this page, then read the verified fixes contributed by other Heavy Truck owners — the answer marked "Verified Cause" worked for the original poster.

OBDIY

OBD-II

P0038

HO2S Heater Control Circuit High (Bank 1 Sensor 2)

What it means

The engine control module (ECM) detects a high voltage condition or short to power in the heater circuit of the downstream oxygen sensor. This circuit is responsible for bringing the sensor to operating temperature quickly to monitor catalyst efficiency.