What is the most likely cause of a P0158 code on a Chevrolet Corvette C7?

On the C7 Corvette, a P0158 code indicates "Bank 2 Sensor 2 High Voltage." This points directly to a fault in the passenger side downstream oxygen sensor, which is located just aft of the catalytic converter ⁸. The code sets when the sensor has an open circuit or is shorted to voltage.

Difficulty: Easy Safety Warning: You will be working under the car around the exhaust. Ensure the vehicle is properly supported on jack stands or a lift, and wait until the exhaust is completely cold to avoid severe burns.

How to Diagnose It

Before throwing parts at it, you can verify the sensor is dead using a scan tool that reads live data:

1. Put the car in "Service Mode" (ignition ON, engine OFF). To do this on a C7, keep your foot OFF the brake and push the start button for about 5 seconds until the green light illuminates ⁸.
2. Connect your scan tool, pull up the live data stream, and find the voltage reading for the B2S2 O2 sensor.
3. With the engine cold and the ignition on, a healthy sensor should show a bias voltage of exactly 450mV ⁸.
4. If it reads significantly higher or shows a short/open, the sensor needs to be replaced.

Replacement Procedure

If the sensor is bad, C7 owners highly recommend sticking exclusively to an OEM GM replacement sensor to avoid compatibility or calibration issues ⁸.

The rest of the replacement is standard automotive practice:

1. Disconnect the negative battery terminal.
2. Follow the pigtail wiring up from the sensor to the main harness and disconnect the plug.
3. Use a standard 7/8" (22mm) O2 sensor socket or a wrench to break the old sensor loose and unthread it.
4. Thread the new OEM sensor in by hand to ensure you don't cross-thread the exhaust bung.

I don't have a verified torque figure for the O2 sensors on this exact platform, so don't take a number from me on it—check the factory service manual if you want to use a torque wrench. The standard procedure is to ensure the threads have a light coating of high-temp anti-seize (OEM sensors usually come pre-coated), thread it in by hand, and then snug it down firmly with your wrench so it seals without damaging the threads. Plug the harness back in, reconnect the battery, and clear the code.