What Does P2233 Mean?
The signal wire from the oxygen sensor after the catalytic converter (Bank 1, Sensor 3) has developed an internal short to its heater circuit. This creates cross-contamination between the signal and heater power, preventing accurate readings.
Common Causes
65%
Failed oxygen sensor with internal short between signal and heater elements
20%
Damaged or melted wiring harness near exhaust causing wire-to-wire short
10%
Corrosion in O2 sensor connector allowing cross-circuit contamination
5%
PCM internal driver circuit failure
Diagnostic Steps
1
Visually inspect O2 sensor and wiring harness for heat damage, melting, or physical damage
2
Disconnect O2 sensor connector and measure resistance between signal wire and heater circuit wires; should show infinite resistance
3
Inspect connector terminals for corrosion, melting, or carbon tracking
4
If wiring tests good, replace O2 sensor and retest
5
If problem persists with new sensor and good wiring, test PCM O2 sensor circuits
Estimated Repair Cost
$150 - $400
Parts + labor, varies by vehicle and location
The signal wire from the oxygen sensor after the catalytic converter (Bank 1, Sensor 3) has developed an internal short to its heater circuit. This creates cross-contamination between the signal and heater power, preventing accurate readings.
The most common cause of P2233 (O2 Sensor Signal Circuit Shorted to Heater Circuit Bank 1 Sensor 3) is: Failed oxygen sensor with internal short between signal and heater elements
Typical repair costs for P2233 range from $150 to $400, depending on the vehicle, location, and whether you do it yourself or go to a shop.
Vehicle is safe to drive short-term but emissions monitoring is compromised. May cause failed emissions tests and slightly reduced fuel economy.
Start by connecting an OBD2 scanner to read the code and any freeze frame data. Then follow the diagnostic steps specific to P2233 to identify the root cause.
OBDHut Mobile App
Scan codes directly from your car with the OBDHut app.
Coming Soon
Quick Info
Category
Powertrain
System
Emissions Control System
Difficulty
Type
Generic (SAE)
Recommended Tools
OBD2 Scanner
A quality scan tool helps you read codes, view live data, and clear faults.
