What it means
The ECU detects an electrical fault in the heater circuit of the downstream O2 sensor on bank 2. Heater current out of range — open or shorted heater element, blown fuse, or wiring fault.
At a glance
- Usually lights the check-engine light
- Affects emissions; the car can fail an emissions test
How it works
Bank 2 Sensor 2 is the downstream oxygen sensor on the engine's second bank, and its heater warms the sensing element after startup. P0162 indicates that the ECU has detected an electrical problem in this heater circuit, such as an open heater or a supply or wiring fault.
Common causes
Most likely first.
- Heater element open
- Heater fuse blown
Symptoms
- Check engine light on after several drive cycles
- Slightly increased fuel consumption during cold start
- Delayed entry into closed-loop fuel control
- Failed emissions inspection (lambda readiness)
How to diagnose it
- Use freeze-frame data and live data to confirm the heater fault and note whether it occurs during cold-start operation.
- Inspect the Bank 2 Sensor 2 connector and heater wiring for corrosion, pin damage, chafing, or melted insulation.
- Check the heater fuse and circuit power supply where applicable.
- Test the heater element and circuit continuity, checking for shorts or opens against the manufacturer's specification.
- If the supply and wiring pass, test the Bank 2 Sensor 2 heater itself before replacing the sensor.
Common fixes
- Repair a loose or corroded Bank 2 Sensor 2 heater connector.
- Repair an open, shorted, or heat-damaged heater wire.
- Replace a blown heater fuse after identifying the underlying cause.
- Replace Bank 2 Sensor 2 if its heater fails the specified electrical tests.
Can I keep driving?
The car is generally driveable, but the heater fault can delay sensor readiness and cause an emissions inspection failure. Have it repaired soon, particularly if the check-engine light is accompanied by poor running.
A code shows where the control module detected a fault, not always which part failed. Check the causes in order and confirm with a test before replacing parts. Have several codes? Check them together
This is a generic code: it means the same on every make. The car’s maker may add more detail in its own service information.