Symptoms

- Engine Light ON (or Service Engine Soon Warning Light)

Possible Causes

- Heated Oxygen Sensor (H2OS) Bank 1 Sensor 2 circuit open shorted to ground - Heated Oxygen Sensor (H2OS) Bank 1 Sensor 2 circuit poor electrical connection - Faulty Heated Oxygen Sensor (H2OS) Bank 1 Sensor 2 circuit - Heated Oxygen Sensor (H2OS) Bank 1 Sensor 2 circuit fuse - Faulty Engine Control Module (ECM)

When Detected

The P0038 is set when the ECM detects an excessively high voltage through the heated oxygen sensor heater circuit

Tech Notes

HO2S Heater Control Circuit High Bank 1 Sensor 2 is the generic definition for the P0038; however your vehicle's manufacturer may have a different definition and information for the P0038 code.

Description

Oxygen Sensors (O2S) or Heated Oxygen Sensors (HO2S) need to reach a minimum operating temperature of 750 degrees F to produce an accurate voltage signal. The faster the heated oxygen sensor reaches that temperature the faster the sensor will start sending an accurate signal to the Engine Control Module (ECM). In order to achieve the require temperature, a heater element is included inside the heated oxygen sensor. The ECM controls the heated oxygen sensor heater element based on signals from the engine coolant temperature and engine load. The ECM controls the heater element circuit by allowing current flow to ground. The ECM monitors the voltage signal received through the heater element circuit and determines the state of the circuit by comparing the voltage detected with the factory specifications.

Information For Specific Makes

P0038 AUDI P0038 BMW P0038 CHRYSLER P0038 DODGE P0038 HYUNDAI P0038 INFINITI P0038 JEEP P0038 KIA P0038 LEXUS P0038 MAZDA P0038 MITSUBISHI P0038 NISSAN P0038 SCION P0038 SUBARU P0038 SUZUKI P0038 TOYOTA P0038 VOLKSWAGEN