Knock Sensor 2 Circuit High Input (Bank 2)
The P0333 code indicates that the Engine Control Module (ECM) has detected a voltage signal from the knock sensor 2 (located on bank 2) that is higher than the expected range. This sensor detects engine knocking or pinging and sends a signal to the ECM to adjust ignition timing. A high input suggests a short circuit to voltage, a faulty sensor, or wiring issues. Bank 2 refers to the side of the engine opposite cylinder #1.
1. Most Common Causes
- Faulty knock sensor 2 on bank 2 (internal short circuit)
- Signal wire shorted to battery voltage (B+)
- Open circuit in the signal wire causing a high pull-up voltage reading
- Damaged, corroded, or loose terminals in the sensor connector
- Internal PCM failure (rare)
2. Symptoms You Will Notice
- Check Engine Light illuminated
- Reduced engine power or hesitation
- Poor fuel economy
- Engine knocking or pinging noise
3. Step-by-Step Diagnosis
Step 1: Scan for codes and record freeze frame data.
Step 2: Visually inspect knock sensor 2 wiring and connector for damage or corrosion.
Step 3: Test sensor resistance and voltage with a multimeter (should be around 2.5V with engine off).
Step 4: Check for shorts to power or ground in the circuit.
Step 5: Replace knock sensor 2 if all wiring tests pass.
4. Frequently Asked Questions
Is it safe to drive with this code?▼
It is not recommended to drive long distances as the ECM may not properly adjust timing, potentially causing engine damage from knocking.
How much does it cost to fix?▼
Repair costs typically range from $150 to $400, including parts and labor. The sensor itself costs $50-$150, and labor can be $100-$250 depending on accessibility.
5. Commonly Affected Makes
This is a generic OBD2 code, potentially applicable to any manufacturer using this diagnostic standard.