P0038 TOYOTA -

Question

replaced o2 sensor,light comes on with P003 code when engine is cold

Answer 1

Hi there,

This code is for the heater circuit in the O2 sensor. Since replacing the sensor didn't resolve the issue, check the fuse box under the hood for a bad heater fuse. These are listed on the cover, if the fuse is blown you will continue to get this code.