O2 Sensor Reference Voltage Circuit High Bank 1 Sensor 1
The P2246 code indicates that the oxygen sensor (O2S) reference voltage circuit for Bank 1 Sensor 1 is higher than expected. This sensor is located upstream of the catalytic converter and monitors air-fuel ratio. The reference voltage is typically 0.45 volts; a high reading suggests a short to voltage, faulty sensor, or wiring issue. This can cause incorrect fuel trim adjustments, leading to poor engine performance and increased emissions.
01. Most Common Causes
- Short to voltage in the O2 sensor reference circuit
- Faulty O2 sensor (Bank 1 Sensor 1)
- Damaged wiring or connector
- Corroded terminals
- ECM issue (rare)
02. Symptoms You Will Notice
- Check Engine Light illuminated
- Poor fuel economy
- Rough idle or hesitation
- Failed emissions test
03. Step-by-Step Diagnosis
Step 1: Scan for codes and record freeze frame data.
Step 2: Visually inspect O2 sensor wiring and connector for damage or corrosion.
Step 3: Measure reference voltage at sensor connector (should be ~0.45V with key on engine off).
Step 4: If voltage is high, disconnect sensor and check for short to voltage in harness.
Step 5: If harness is okay, replace O2 sensor (Bank 1 Sensor 1).
04. Commonly Affected Makes
05. Frequently Asked Questions
Is it safe to drive with this code?▼
You can drive short distances, but it may cause poor performance and increased emissions. Prolonged driving can damage the catalytic converter.
How much does it cost to fix?▼
Typically $150-$300 including parts and labor, depending on vehicle and shop rates.